[Federal Register Volume 84, Number 176 (Wednesday, September 11, 2019)]
[Proposed Rules]
[Pages 48006-48036]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2019-19050]
[[Page 48005]]
Vol. 84
Wednesday,
No. 176
September 11, 2019
Part II
Department of Energy
-----------------------------------------------------------------------
10 CFR Part 431
Energy Conservation Standards for Computer Room Air Conditioners and
Dedicated Outdoor Air Systems; Proposed Rule
Federal Register / Vol. 84 , No. 176 / Wednesday, September 11, 2019
/ Proposed Rules
[[Page 48006]]
-----------------------------------------------------------------------
DEPARTMENT OF ENERGY
10 CFR Part 431
[EERE-2017-BT-STD-0017]
RIN 1904-AD92
Energy Conservation Standards for Computer Room Air Conditioners
and Dedicated Outdoor Air Systems
AGENCY: Office of Energy Efficiency and Renewable Energy, Department of
Energy.
ACTION: Notice of data availability and request for information.
-----------------------------------------------------------------------
SUMMARY: The U.S. Department of Energy (DOE) is publishing an analysis
of the energy savings potential of amended industry consensus standards
for certain classes of computer room air conditioners (CRACs) and new
industry standards for dedicated outdoor air systems (DOASes), which
are types of commercial and industrial equipment. The Energy Policy and
Conservation Act of 1975, as amended (EPCA), requires DOE to evaluate
and assess whether there is a need to update its energy conservation
standards following changes to the relevant industry consensus
standards in the American Society of Heating, Refrigerating and Air-
Conditioning Engineers (ASHRAE) Standard 90.1 (ASHRAE Standard 90.1).
Additionally under EPCA, DOE must review the existing standards for
this equipment at least once every six years and publish either a
notice of proposed rulemaking (NOPR) to propose new standards or a
notice of determination that the existing standards do not need to be
amended. Accordingly, DOE is also initiating an effort to determine
whether to amend the current energy conservation standards for classes
of CRACs for which DOE has tentatively determined that the updated
ASHRAE Standard 90.1 levels are not more stringent than the current
Federal standards. This document solicits information from the public
to help DOE determine whether amended standards for CRACs and new
standards for DOASes would result in significant energy savings and
whether such standards would be technologically feasible and
economically justified. DOE welcomes written comments from the public
on any subject within the scope of this document (including topics not
raised in this document), as well as the submission of data and other
relevant information.
DATES: Written comments and information are requested and will be
accepted on or before October 28, 2019.
ADDRESSES: Interested persons are encouraged to submit comments using
the Federal eRulemaking Portal at http://www.regulations.gov. Follow
the instructions for submitting comments. Alternatively, interested
persons may submit comments, identified by docket number EERE-2017-BT-
STD-0017 by any of the following methods:
1. Federal eRulemaking Portal: http://www.regulations.gov. Follow
the instructions for submitting comments.
2. Email: [email protected]. Include the
docket number EERE-2017-BT-STD-0017 in the subject line of the message.
3. Postal Mail: Appliance and Equipment Standards Program, U.S.
Department of Energy, Building Technologies Office, Mailstop EE-5B,
Energy Conservation Standards NODA and RFI for Certain Categories of
Commercial Air-Conditioning and Heating Equipment, 1000 Independence
Avenue SW, Washington, DC 20585-0121. If possible, please submit all
items on a compact disc (``CD''), in which case it is not necessary to
include printed copies.
4. Hand Delivery/Courier: Appliance and Equipment Standards
Program, U.S. Department of Energy, Building Technologies Office, 950
L'Enfant Plaza SW, 6th Floor, Washington, DC 20024. Telephone: (202)
287-1445. If possible, please submit all items on a CD, in which case
it is not necessary to include printed copies.
No telefacsimilies (faxes) will be accepted. For detailed
instructions on submitting comments and additional information on the
rulemaking process, see section V of this document (Public
Participation).
Docket: The docket for this activity, which includes Federal
Register notices, comments, and other supporting documents/materials,
is available for review at http://www.regulations.gov (search EERE-
2017-BT-STD-0017). All documents in the docket are listed in the http://www.regulations.gov index. However, some documents listed in the
index, such as those containing information that is exempt from public
disclosure, may not be publicly available.
The docket web page can be found at: https://www.regulations.gov/docket?D=EERE-2017-BT-STD-0017. The docket web page contains
instructions on how to access all documents, including public comments,
in the docket. See section V of this document, Public Participation,
for information on how to submit comments through http://www.regulations.gov.
FOR FURTHER INFORMATION CONTACT: Ms. Catherine Rivest, U.S. Department
of Energy, Office of Energy Efficiency and Renewable Energy, Building
Technologies Office, EE-5B, 1000 Independence Avenue SW, Washington, DC
20585-0121. Telephone: (202) 586-7335. Email:
[email protected].
Mr. Eric Stas, U.S. Department of Energy, Office of the General
Counsel, GC-33, 1000 Independence Avenue SW, Washington, DC 20585.
Telephone: (202) 586-5827. Email: [email protected].
For further information on how to submit a comment or review other
public comments and the docket, contact the Appliance and Equipment
Standards Program staff at (202) 287-1445 or by email:
[email protected].
SUPPLEMENTARY INFORMATION:
Table of Contents
I. Introduction
A. Authority
B. Purpose of the Notice of Data Availability
C. Rulemaking Background
II. Discussion of Changes in ASHRAE Standard 90.1-2016
A. Computer Room Air Conditioners
1. Methodology for Efficiency and Capacity Crosswalk Analyses
a. General
b. Increase in Return Air Dry-Bulb Temperature From 75 [deg]F to
85 [deg]F
c. Decrease in Entering Water Temperature for Water-Cooled CRACs
d. Changes in External Static Pressure Requirements for Upflow
Ducted CRACs
e. Power Adder To Account for Pump and Heat Rejection Fan Power
in NSenCOP Calculation for Water-Cooled and Glycol-Cooled CRACs
f. Calculating Overall Changes in Measured Efficiency and
Capacity From Test Procedure Changes
2. Crosswalk Results
3. CRAC Standards Amended Under ASHRAE Standard 90.1
B. Dedicated Outdoor Air Systems
C. Test Procedures
III. Analysis of Standards Amended and Newly Established by ASHRAE
Standard 90.1-2016
A. Annual Energy Use
1. Computer Room Air Conditioners
a. Equipment Classes and Analytical Scope
b. Efficiency Levels
c. Analysis Method and Annual Energy Use Results
2. Dedicated Outdoor Air Systems
a. Equipment Classes and Analytical Scope
b. Efficiency Levels
c. Energy Use Simulations and Annual Energy Use Results
B. Shipments
1. Computer Room Air Conditioners
2. Dedicated Outdoor Air Systems
C. No-New-Standards-Case Efficiency Distribution
D. Other Analytical Inputs
1. Equipment Lifetime
[[Page 48007]]
2. Compliance Dates and Analysis Period
E. Other Energy Conservation Standards Topics
1. Market Failures
2. Network Mode/``Smart'' Equipment
3. Other
F. Estimates of Potential Energy Savings
IV. Review Under Six-Year Lookback Provisions: Requested Information
V. Public Participation
A. Submission of Comments
B. Issues on Which DOE Seeks Comment
VI. Approval of the Office of the Secretary
I. Introduction
A. Authority
The Energy Policy and Conservation Act of 1975, as amended
(``EPCA''; 42 U.S.C. 6291 et seq.),\1\ established the Energy
Conservation Program for Consumer Products Other Than Automobiles.
Title III, Part C \2\ of EPCA, Public Law 94-163 (42 U.S.C. 6311-6317,
as codified), added by Public Law 95-619, Title IV, Sec. 441(a),
established the Energy Conservation Program for Certain Industrial
Equipment. This covered equipment includes small, large, and very large
commercial package air conditioning and heating equipment, which
includes CRACs and DOASes, the subjects of this document. (42 U.S.C.
6311(1)(B)-(D))
---------------------------------------------------------------------------
\1\ All references to EPCA in this document refer to the statute
as amended through America's Water Infrastructure Act of 2018,
Public Law 115-270 (Oct. 23, 2018).
\2\ For editorial reasons, upon codification in the U.S. Code,
Part C was redesignated Part A-1.
---------------------------------------------------------------------------
Pursuant to EPCA, DOE's energy conservation program consists
essentially of four parts: (1) Testing, (2) labeling, (3) Federal
energy conservation standards, and (4) certification and enforcement
procedures. Relevant provisions of the EPCA specifically include
definitions (42 U.S.C. 6311), energy conservation standards (42 U.S.C.
6313), test procedures (42 U.S.C. 6314), labeling provisions (42 U.S.C.
6315), and the authority to require information and reports from
manufacturers (42 U.S.C. 6316).
Federal energy efficiency requirements for covered equipment
established under EPCA generally supersede State laws and regulations
concerning energy conservation testing, labeling, and standards. (42
U.S.C. 6316(a) and (b); 42 U.S.C. 6297) DOE may, however, grant waivers
of Federal preemption for particular State laws or regulations, in
accordance with the procedures and other provisions set forth under 42
U.S.C. 6316(b)(2)(D).
In EPCA, Congress initially set mandatory energy conservation
standards for certain types of commercial heating, air-conditioning,
and water-heating equipment. (42 U.S.C. 6313(a)) Specifically, the
statute sets standards for small, large, and very large commercial
package air conditioning and heating equipment, packaged terminal air
conditioners (PTACs) and packaged terminal heat pumps (PTHPs), warm-air
furnaces, packaged boilers, storage water heaters, instantaneous water
heaters, and unfired hot water storage tanks. Id. In doing so, EPCA
established Federal energy conservation standards at levels that
generally corresponded to the levels in ASHRAE Standard 90.1, Energy
Standard for Buildings Except Low-Rise Residential Buildings, as in
effect on October 24, 1992 (i.e., ASHRAE Standard 90.1-1989), for each
type of covered equipment listed in 42 U.S.C. 6313(a).
In acknowledgement of technological changes that yield energy
efficiency benefits, Congress further directed DOE through EPCA to
consider amending the existing Federal energy conservation standard for
each type of equipment listed, each time ASHRAE amends Standard 90.1
with respect to such equipment. (42 U.S.C. 6313(a)(6)(A)) When
triggered in this manner, DOE must undertake and publish an analysis of
the energy savings potential of amended energy efficiency standards,
and amend the Federal standards to establish a uniform national
standard at the minimum level specified in the amended ASHRAE Standard
90.1, unless DOE determines that there is clear and convincing evidence
to support a determination that a more-stringent standard level as a
national standard would produce significant additional energy savings
and be technologically feasible and economically justified. (42 U.S.C.
6313(a)(6)(A)(ii)) If DOE decides to adopt as a national standard the
minimum efficiency levels specified in the amended ASHRAE Standard
90.1, DOE must establish such standard not later than 18 months after
publication of the amended industry standard. (42 U.S.C.
6313(a)(6)(A)(ii)(I)) However, if DOE determines, supported by clear
and convincing evidence, that a more-stringent uniform national
standard would result in significant additional conservation of energy
and is technologically feasible and economically justified, then DOE
must establish such more-stringent uniform national standard not later
than 30 months after publication of the amended ASHRAE Standard
90.1.\3\ (42 U.S.C. 6313(a)(6)(A)(ii)(II) and (B))
---------------------------------------------------------------------------
\3\ In determining whether a more-stringent standard is
economically justified, EPCA directs DOE to determine, after
receiving views and comments from the public, whether the benefits
of the proposed standard exceed the burdens of the proposed standard
by, to the maximum extent practicable, considering the following:
(1) The economic impact of the standard on the manufacturers and
consumers of the products subject to the standard;
(2) The savings in operating costs throughout the estimated
average life of the product compared to any increases in the initial
cost or maintenance expense;
(3) The total projected amount of energy savings likely to
result directly from the standard;
(4) Any lessening of the utility or the performance of the
products likely to result from the standard;
(5) The impact of any lessening of competition, as determined in
writing by the Attorney General, that is likely to result from the
standard;
(6) The need for national energy conservation; and
(7) Other factors the Secretary considers relevant.
(42 U.S.C. 6313(a)(6)(B)(ii)).
---------------------------------------------------------------------------
Although EPCA does not explicitly define the term ``amended'' in
the context of what type of revision to ASHRAE Standard 90.1 would
trigger DOE's obligation, DOE's longstanding interpretation has been
that the statutory trigger is an amendment to the standard applicable
to that equipment under ASHRAE Standard 90.1 that increases the energy
efficiency level for that equipment. See 72 FR 10038, 10042 (March 7,
2007). In other words, if the revised ASHRAE Standard 90.1 leaves the
energy efficiency level unchanged (or lowers the energy efficiency
level), as compared to the energy efficiency level specified by the
uniform national standard adopted pursuant to EPCA, regardless of the
other amendments made to the ASHRAE Standard 90.1 requirement (e.g.,
the inclusion of an additional metric), DOE has stated that it does not
have the authority to conduct a rulemaking to consider a higher
standard for that equipment pursuant to 42 U.S.C. 6313(a)(6)(A). See 74
FR 36312, 36313 (July 22, 2009) and 77 FR 28928, 28937 (May 16, 2012).
However, DOE notes that Congress adopted amendments to these provisions
related to ASHRAE Standard 90.1 equipment under the American Energy
Manufacturing Technical Corrections Act (Pub. L. 112-210 (Dec. 18,
2012); ``AEMTCA''). In relevant part, DOE is prompted to act whenever
ASHRAE Standard 90.1 is amended with respect to ``the standard levels
or design requirements applicable under that standard'' to any of the
enumerated types of commercial air conditioning, heating, or water
heating equipment. (42 U.S.C. 6313(a)(6)(A)(i)).
EPCA does not detail the exact type of amendment that serves as a
triggering event. However, DOE has considered whether its obligation is
triggered in the context of whether the specific ASHRAE Standard 90.1
requirement on which the most current Federal requirement is
[[Page 48008]]
based is amended (i.e., the regulatory metric). For example, if an
amendment to ASHRAE Standard 90.1 changed the metric for the standard
on which the Federal requirement was based, DOE would perform a
crosswalk analysis to determine whether the amended metric under ASHRAE
Standard 90.1 resulted in an energy efficiency level that was more
stringent than the current DOE standard. Conversely, if an amendment to
ASHRAE Standard 90.1 were to add an additional metric by which a class
of equipment is to be evaluated, but did not amend the requirement that
is in terms of the metric on which the Federal requirement was based,
DOE would not consider its obligation triggered.\4\
---------------------------------------------------------------------------
\4\ See the May 16, 2012, final rule for small, large, and very
large water-cooled and evaporatively-cooled commercial package air
conditioners, and variable refrigerant flow (VRF) water-source heat
pumps with cooling capacity less than 17,000 Btu/h, in which DOE
states that ``if the revised ASHRAE Standard 90.1 leaves the
standard level unchanged or lowers the standard, as compared to the
level specified by the national standard adopted pursuant to EPCA,
DOE does not have the authority to conduct a rulemaking to consider
a higher standard for that equipment pursuant to 42 U.S.C.
6313(a)(6)(A). 77 FR 28928, 28929 (emphasis added). See also, 74 FR
36312, 36313 (July 22, 2009).
---------------------------------------------------------------------------
In addition, DOE has explained that its authority to adopt an
ASHRAE amendment is limited based on the definition of ``energy
conservation standard.'' 74 FR 36312, 36322 (July 22, 2009). In
general, an ``energy conservation standard'' is limited, per the
statutory definition, to either a performance standard or a design
requirement. (42 U.S.C. 6311(18)) Informed by the ``energy conservation
standard'' definition, DOE has stated that adoption of an amendment to
ASHRAE Standard 90.1 ``that establishes both a performance standard and
a design requirement is beyond the scope of DOE's legal authority, as
would be a standard that included more than one design requirement.''
74 FR 36312, 36322 (July 22, 2009).
As noted, the ASHRAE Standard 90.1 provision in EPCA acknowledges
technological changes that yield energy efficiency benefits, as well as
continuing development of industry standards and test methods.
Amendments to a uniform national standard provide Federal requirements
that continue to reflect energy efficiency improvements identified by
industry. Amendments to a uniform national standard that reflect the
relevant amended versions of ASHRAE Standard 90.1 would also help
reduce compliance and test burdens on manufacturers by harmonizing the
Federal requirements, when appropriate, with industry best practices.
This harmonization would be further facilitated by establishing not
only consistent energy efficiency levels and design requirements
between ASHRAE Standard 90.1 and the Federal requirements, but
comparable metrics as well.
As stated previously, DOE has limited its review under the ASHRAE
Standard 90.1 provisions in EPCA to the equipment classes that are
subject to the ASHRAE Standard 90.1 amendment. DOE has stated that if
ASHRAE has not amended a standard for an equipment class subject to 42
U.S.C. 6313, there is no change that would require action by DOE to
consider amending the uniform national standard to maintain consistency
with ASHRAE Standard 90.1. See, 72 FR 10038, 10042 (March 7, 2007); 77
FR 36312, 36320-36321 (July 22, 2009); 80 FR 42614, 42617 (July 17,
2015).
In those situations where ASHRAE has not acted to amend the levels
in Standard 90.1 for the equipment types enumerated in the statute,
EPCA also provides for a 6-year-lookback to consider the potential for
amending the uniform national standards. (42 U.S.C. 6313(a)(6)(C))
Specifically, pursuant to the amendments to EPCA under AEMTCA, DOE is
required to conduct an evaluation of each class of covered equipment in
ASHRAE Standard 90.1 ``every 6 years'' to determine whether the
applicable energy conservation standards need to be amended. (42 U.S.C.
6313(a)(6)(C)(i)) DOE must publish either a notice of proposed
rulemaking (NOPR) to propose amended standards or a notice of
determination that existing standards do not need to be amended. (42
U.S.C. 6313(a)(6)(C)) In proposing new standards under the 6-year
review, DOE must undertake the same considerations as if it were
adopting a standard that is more stringent than an amendment to ASHRAE
Standard 90.1. (42 U.S.C. 6313(a)(6)(C)(i)(II)) This is a separate
statutory review obligation, as differentiated from the obligation
triggered by an ASHRAE Standard 90.1 amendment. While the statute
continues to defer to ASHRAE's lead on covered equipment subject to
Standard 90.1, it does allow for a comprehensive review of all such
equipment and the potential for adopting more-stringent standards,
where supported by the requisite clear and convincing evidence. That
is, DOE interprets ASHRAE's not amending Standard 90.1 with respect to
a product or equipment type as ASHRAE's determination that the standard
applicable to that product or equipment type is already at an
appropriate level of stringency, and DOE will not amend that standard
unless there is clear and convincing evidence that a more stringent
level is justified.
As a preliminary step in the process of reviewing the changes to
ASHRAE Standard 90.1, EPCA directs DOE to publish in the Federal
Register for public comment an analysis of the energy savings potential
of amended standards within 180 days after ASHRAE Standard 90.1 is
amended with respect to any of the covered equipment specified under 42
U.S.C. 6313(a). (42 U.S.C. 6313(a)(6)(A)).
On October 26, 2016, ASHRAE officially released for distribution
and made public ASHRAE Standard 90.1-2016. This action by ASHRAE
triggered DOE's obligations under 42 U.S.C. 6313(a)(6), as outlined
previously. This notice of data availability (NODA) presents the
analysis of the energy savings potential of amended energy efficiency
standards, as required under 42 U.S.C. 6313(a)(6)(A)(i). DOE is also
taking this opportunity to collect data and information regarding other
CRAC equipment classes for which it was not triggered by ASHRAE but for
which DOE plans to conduct a concurrent 6-year-lookback review. (42
U.S.C. 6313(a)(6)(C)) Such information will help DOE inform its
decisions, consistent with its obligations under EPCA.
CRAC Issue 1: DOE seeks comment on whether, in the context of
its consideration of more-stringent standards, there have been
sufficient technological or market changes for CRACs since the most
recent standards update that may justify a new rulemaking to
consider more-stringent standards. Specifically, DOE seeks data and
information that could enable the agency to determine whether DOE
should propose a ``no new standard'' determination because a more-
stringent standard: (1) Would not result in significant additional
savings of energy; (2) is not technologically feasible; (3) is not
economically justified; or (4) any combination of the foregoing.
B. Purpose of the Notice of Data Availability
As explained previously, DOE is publishing this NODA as a
preliminary step pursuant to EPCA's requirements for DOE to consider
amended standards for certain categories of commercial equipment
covered by ASHRAE Standard 90.1, whenever ASHRAE amends its standard to
increase the energy efficiency level for an equipment class within a
given equipment category. Specifically, this NODA presents for public
comment DOE's analysis of the potential energy savings for amended
national energy conservation standards for these categories of
commercial equipment
[[Page 48009]]
based on: (1) The amended efficiency levels contained within ASHRAE
Standard 90.1-2016, and (2) more-stringent efficiency levels. DOE
describes these analyses and preliminary conclusions and seeks input
from interested parties, including the submission of data and other
relevant information. DOE is also taking the opportunity to consider
the potential for more-stringent standards for the other equipment
classes of the subject equipment types (i.e., where DOE was not
triggered) under EPCA's 6-year-lookback authority.
DOE carefully examined the changes for equipment in ASHRAE Standard
90.1 in order to thoroughly evaluate the amendments in ASHRAE 90.1-
2016, thereby permitting DOE to determine what action, if any, is
required under its statutory mandate. DOE also will carefully examine
the energy savings potential for other equipment classes where it was
not triggered, so as to conduct a thorough review for an entire
equipment category. Section II of this NODA contains DOE's evaluation
of the amendments in ASHRAE 90.1-2016. For equipment classes
preliminarily determined to have increased efficiency levels or changes
in design requirements in ASHRAE Standard 90.1-2016, DOE subjected that
equipment to further analysis as discussed in section III of this NODA.
Section IV requests comment for those equipment classes for which
efficiency levels and design requirements have not been increased or
changed in ASHRAE 90.1-2016, but are undergoing review under EPCA's 6-
year lookback authority.
In summary, the energy savings analysis presented in this NODA is a
preliminary step required under 42 U.S.C. 6313(a)(6)(A)(i). DOE is also
treating it as an opportunity to gather information regarding its
obligations under 42 U.S.C. 6313(a)(6)(C). After review of the public
comments on this NODA, if DOE determines that the amended efficiency
levels in ASHRAE Standard 90.1-2016 have the potential for additional
energy savings for classes of equipment currently covered by uniform
national standards, DOE will commence a rulemaking to amend standards
based upon the efficiency levels in ASHRAE Standard 90.1-2016 or, where
supported by clear and convincing evidence, consider more-stringent
efficiency levels that would be expected to result in significant
additional conservation of energy and are technologically feasible and
economically justified. If DOE determines it appropriate to conduct
such a rulemaking under the statute, DOE will address the anti-
backsliding provision,\5\ and if DOE determines it appropriate to
conduct a rulemaking to establish more-stringent efficiency levels, DOE
will also address the general rulemaking requirements applicable under
42 U.S.C. 6313(a)(6)(B), such as, the criteria for making a
determination of economic justification as to whether the benefits of
the proposed standard exceed the burden of the proposed standard,\6\
and the prohibition on making unavailable existing products with
performance characteristics generally available in the United
States.\7\
---------------------------------------------------------------------------
\5\ The anti-backsliding provision mandates that the Secretary
may not prescribe any amended standard that either increases the
maximum allowable energy use or decreases the minimum required
energy efficiency of a covered product. (42 U.S.C. 6313
(a)(6)(B)(iii)(I)).
\6\ In deciding whether a potential standard's benefits outweigh
its burdens, DOE must consider to the maximum extent practicable,
the following seven factors:
(1) The economic impact on manufacturers and consumers of the
product subject to the standard;
(2) The savings in operating costs throughout the estimated
average life of the product in the type (or class), compared to any
increase in the price, initial charges, or maintenance expenses of
the products likely to result from the standard;
(3) The total projected amount of energy savings likely to
result directly from the standard;
(4) Any lessening of product utility or performance of the
product likely to result from the standard;
(5) The impact of any lessening of competition, as determined in
writing by the Attorney General, likely to result from the standard;
(6) The need for national energy conservation; and
(7) Other factors the Secretary considers relevant.
(42 U.S.C. 6313(a)(6)(B)(ii)(I)-(VII)).
\7\ The Secretary may not prescribe an amended standard if
interested persons have established by a preponderance of evidence
that the amended standard would likely result in unavailability in
the U.S. of any covered product type (or class) of performance
characteristics (including reliability, features, capacities, sizes,
and volumes) that are substantially the same as those generally
available in the U.S. at the time of the Secretary's finding. (42
U.S.C. 6313(a)(6)(B)(iii)(II)).
---------------------------------------------------------------------------
C. Rulemaking Background
EPCA defines ``commercial package air conditioning and heating
equipment'' as air-cooled, water-cooled, evaporatively-cooled, or water
source (not including ground water source) electrically operated,
unitary central air conditioners and central air conditioning heat
pumps for commercial application. (42 U.S.C. 6311(8)(A); 10 CFR 431.92)
EPCA further classifies ``commercial package air conditioning and
heating equipment'' into categories based on cooling capacity (i.e.,
small, large, and very large categories). (42 U.S.C. 6311(8)(B)-(D); 10
CFR 431.92) ``Small commercial package air conditioning and heating
equipment'' means equipment rated below 135,000 Btu per hour (cooling
capacity). (42 U.S.C. 6311(8)(B); 10 CFR 431.92) ``Large commercial
package air conditioning and heating equipment'' means equipment rated:
(i) At or above 135,000 Btu per hour; and (ii) below 240,000 Btu per
hour (cooling capacity). (42 U.S.C. 6311(8)(C); 10 CFR 431.92) ``Very
large commercial package air conditioning and heating equipment'' means
equipment rated: (i) At or above 240,000 Btu per hour; and (ii) below
760,000 Btu per hour (cooling capacity). (42 U.S.C. 6311(8)(D); 10 CFR
431.92) DOE generally refers to these broad classifications as
``equipment types.''
Pursuant to its authority under EPCA (42 U.S.C. 6313(a)(6)(A)) and
in response to updates to ASHRAE Standard 90.1, DOE has established
additional categories of equipment that meet the EPCA definition of
``commercial package air conditioning and heating equipment,'' but
which EPCA did not expressly identify. These equipment categories
include CRACs (see 10 CFR 431.92 and 10 CFR 431.97) and DOASes, for
which ASHRAE Standard 90.1-2016 established a new category. Within
these additional equipment categories, further distinctions are made at
the equipment class level based on capacity and other equipment
attributes.
DOE's current energy conservation standards for 30 equipment
classes of CRACs are codified at 10 CFR 431.97. DOE defines ``computer
room air conditioner'' as a commercial package air-conditioning and
heating equipment (packaged or split) that is: Used in computer rooms,
data processing rooms, or other information technology cooling
applications; rated for sensible coefficient of performance (SCOP) and
tested in accordance with 10 CFR 431.96, and is not a covered product
under 42 U.S.C. 6291(1)-(2) and 6292. A computer room air conditioner
may be provided with, or have as available options, an integrated
humidifier, temperature, and/or humidity control of the supplied air,
and reheating function. 10 CFR 431.92.
DOE's regulations include test procedures and energy conservation
standards that apply to the current CRAC equipment classes that are
differentiated by condensing system type (air-cooled, water-cooled,
water-cooled with fluid economizer, glycol-cooled, or glycol-cooled
with fluid economizer), net sensible cooling capacity (less than 65,000
Btu/h, greater than or equal to 65,000 Btu/h and less than 240,000 Btu/
h, or greater than or equal to 240,000 Btu/h and less than 760,000 Btu/
h), and direction of
[[Page 48010]]
conditioned air over the cooling coil (upflow or downflow). 10 CFR
431.96 and 10 CFR 431.97, respectively.
DOE's test procedure for CRACs, set forth at 10 CFR 431.96,
currently incorporates by reference ANSI/ASHRAE Standard 127-2007
(``ASHRAE 127-2007''), ``Method of Testing for Rating Computer and Data
Processing Room Unitary Air Conditioners,'' (omit section 5.11), with
additional provisions indicated in 10 CFR 431.96(c) and (e). The energy
efficiency metric is sensible coefficient of performance (SCOP) for all
CRAC equipment classes. ASHRAE 90.1-2016 updated its test procedure
reference for CRACs from ASHRAE 127-2007 to AHRI 1360-2016,
``Performance Rating of Computer and Data Processing Room Air
Conditioners,'' which in turn references ANSI/ASHRAE Standard 127-2012,
``Method of Testing for Rating Computer and Data Processing Room
Unitary Air Conditioners''.
The energy conservation standards for CRACs were most recently
amended through the final rule for energy conservation standards and
test procedures for certain commercial HVAC and water heating equipment
published in the Federal Register on May 16, 2012 (``May 2012 final
rule''). 77 FR 28928. The May 2012 final rule established separate
equipment classes for CRACs and adopted energy conservation standards
that generally correspond to the levels in the 2010 revision of ASHRAE
Standard 90.1 for most of the equipment classes.
As noted previously, on October 26, 2016, ASHRAE officially
released for distribution and made public ASHRAE Standard 90.1-2016.
ASHRAE Standard 90.1-2016 revised the efficiency levels for certain
commercial equipment, including certain classes of CRACs (as discussed
in the following section). Also, as stated, ASHRAE Standard 90.1-2016
established a new category for DOASes.\8\
---------------------------------------------------------------------------
\8\ ASHRAE Standard 90.1-2016 also revised standards for certain
classes of VRF multi-split systems. DOE is addressing VRF multi-
split systems in a separate document, as this equipment is the
subject of a negotiated rulemaking under the auspices of the
Appliance Standards and Rulemaking Federal Advisory Committee
(ASRAC). See, https://www1.eere.energy.gov/buildings/appliance_standards/standards.aspx?productid=71&action=viewlive. For
the remaining equipment, ASHRAE left in place the preexisting levels
(i.e., the efficiency levels specified in EPCA or the efficiency
levels in ASHRAE Standard 90.1-2013).
---------------------------------------------------------------------------
II. Discussion of Changes in ASHRAE Standard 90.1-2016
Before beginning an analysis of the potential energy savings that
would result from adopting a uniform national standard as specified by
ASHRAE Standard 90.1-2016 or more-stringent uniform national standards,
DOE must first determine whether the ASHRAE Standard 90.1-2016 standard
levels actually represent an increase in efficiency above the current
Federal standard levels or whether ASHRAE Standard 90.1-2016 adopted
new design requirements, thereby triggering DOE action.
This section contains a discussion of each equipment class where
the ASHRAE Standard 90.1-2016 efficiency levels differ from the ASHRAE
Standard 90.1-2013 level(s) \9\ (based on a rating metric used in the
relevant Federal energy conservation standards) or where ASHRAE created
new equipment classes, along with DOE's preliminary conclusion
regarding the appropriate action to take with respect to that
equipment. DOE is also examining the other equipment classes for the
triggered equipment categories under its 6-year-lookback authority. (42
U.S.C. 6313(a)(6)(C)).
---------------------------------------------------------------------------
\9\ ASHRAE Standard 90.1-2016 did not change any of the design
requirements for the commercial heating, air conditioning, and water
heating equipment covered by EPCA, so this potential category of
change is not discussed in this section.
---------------------------------------------------------------------------
As noted above, ASHRAE Standard 90.1-2016 adopted efficiency levels
for all CRAC equipment classes in terms of NSenCOP (measured per AHRI
1360-2016), whereas DOE's current standards are in terms of SCOP
(measured per ASHRAE 127-2007). For this NODA, DOE's analysis focuses
on whether DOE has been triggered by ASHRAE 90.1-2016 updates to
minimum efficiency levels for CRACs and whether more-stringent
standards are warranted; DOE will consider whether to adopt the NSenCOP
metric for all CRAC equipment classes as part of the ongoing test
procedure rulemaking. As discussed in detail in the following section,
DOE has conducted a crosswalk analysis of the ASHRAE Standard 90.1
standard levels that rely on NSenCOP and the efficiency levels of the
corresponding Federal energy conservation standard that rely on SCOP to
compare the stringencies. DOE has tentatively determined that the
updates in ASHRAE Standard 90.1-2016 increased the stringency of
efficiency levels for five equipment classes, maintained equivalent
levels for three equipment classes, and reduced stringency for 37
classes of CRACs relative to the current Federal standard. In addition,
ASHRAE Standard 90.1-2016 added efficiency levels for 15 classes of
horizontal-flow \10\ CRACs which do not currently have a Federal
standard.
---------------------------------------------------------------------------
\10\ ``Horizontal flow'' refers to the direction of airflow of
the unit.
---------------------------------------------------------------------------
ASHRAE Standard 90.1-2016 also adopted standards for DOASes, which
previously did not have energy efficiency levels specified. ASHRAE
Standard 90.1-2016 specifies standards for 12 classes of DOASes. As
currently there are no Federal standards for DOASes, no comparison of
efficiency levels to the current DOE standards levels was necessary.
Table II.1 shows the CRAC and DOAS equipment classes provided in
ASHRAE Standard 90.1-2016, the efficiency levels for these classes in
ASHRAE Standard 90.1-2016, and the corresponding efficiency levels in
ASHRAE Standard 90.1-2013 (for CRACs only). For CRACs, Table II.1 also
displays the corresponding existing Federal energy conservation
standards. As noted previously, for CRACs, ASHRAE Standard 90.1-2016
adopted efficiency levels in terms of NSenCOP (based on the AHRI 1360
test procedure), whereas DOE's current standards are in terms of SCOP
(based on the test procedures in ASHRAE 127-2007). DOE performed an
analysis to translate the current DOE standards to NSenCOP values
(``crosswalk analysis''). The crosswalk analysis then allowed DOE to
compare whether the ASHRAE Standard 90.1-2016 efficiency levels are
more stringent than the corresponding Federal standards. (See section
II.A of this NODA for further discussion on the crosswalk analysis
performed for CRACs.) Table II.1 also indicates whether the update in
ASHRAE Standard 90.1-2016 triggers DOE's evaluation as required under
EPCA (i.e., whether the update results in a standard level more
stringent than the current Federal level). For DOASes, there are
currently no Federal standards; therefore, DOE's evaluation as required
under EPCA is triggered for all DOAS efficiency levels added in ASHRAE
Standard 90.1-2016. The remainder of this section assesses each of
these equipment classes and describes whether the amendments in ASHRAE
Standard 90.1-2016 constitute amendments necessitating further analysis
of the potential energy savings from corresponding amendments to the
Federal energy conservation standards.
[[Page 48011]]
Table II.1--Energy Efficiency Levels for CRACs and DOASes in ASHRAE Standard 90.1-2016, and the Corresponding
Levels in ASHRAE Standard 90.1-2013 and the Federal Energy Conservation Standards \1\
----------------------------------------------------------------------------------------------------------------
Energy efficiency
levels in ASHRAE Energy efficiency Federal energy DOE triggered by
ASHRAE standard 90.1-2016 standard 90.1- levels in ASHRAE conservation ASHRAE standard
equipment class \1\ 2013 (as standard 90.1- standards 90.1-2016
corrected) \2\ 2016 amendment?
----------------------------------------------------------------------------------------------------------------
Commercial Package Air-Conditioning and Heating Equipment--Computer Room Air Conditioners 3
----------------------------------------------------------------------------------------------------------------
CRAC, Air-Cooled, <65,000 Btu/h, 2.20 SCOP......... 2.30 NSenCOP...... 2.20 SCOP......... No.\4\
Downflow.
CRAC, Air-Cooled, <65,000 Btu/h, N/A............... 2.45 NSenCOP...... N/A............... Yes.\5\
Horizontal-flow.
CRAC, Air-Cooled, <65,000 Btu/h, 2.09 SCOP......... 2.10 NSenCOP...... 2.09 SCOP......... No.\4\
Upflow Ducted.
CRAC, Air-Cooled, <65,000 Btu/h, 2.09 SCOP......... 2.09 NSenCOP...... 2.09 SCOP......... No.\6\
Upflow Non-Ducted.
CRAC, Air-Cooled, >=65,000 and 2.10 SCOP......... 2.20 NSenCOP...... 2.10 SCOP......... No.\4\
<240,000 Btu/h, Downflow.
CRAC, Air-Cooled, >=65,000 and N/A............... 2.35 NSenCOP...... N/A............... Yes.\5\
<240,000 Btu/h, Horizontal-flow.
CRAC, Air-Cooled, >=65,000 and 1.99 SCOP......... 2.05 NSenCOP...... 1.99 SCOP......... No.\4\
<240,000 Btu/h, Upflow Ducted.
CRAC, Air-Cooled, >=65,000 and 1.99 SCOP......... 1.99 NSenCOP...... 1.99 SCOP......... No.\6\
<240,000 Btu/h, Upflow Non-
Ducted.
CRAC, Air-Cooled, >=240,000 Btu/ 1.90 SCOP......... 2.00 NSenCOP...... 1.90 SCOP......... No.\4\
h and <760,000 Btu/h, Downflow.
CRAC, Air-Cooled, >=240,000 Btu/ N/A............... 2.15 NSenCOP...... N/A............... Yes.\5\
h and <760,000 Btu/h,
Horizontal-flow.
CRAC, Air-Cooled, >=240,000 Btu/ 1.79 SCOP......... 1.85 NSenCOP...... 1.79 SCOP......... No.\4\
h and <760,000 Btu/h, Upflow
Ducted.
CRAC, Air-Cooled, >=240,000 Btu/ 1.79 SCOP......... 1.79 NSenCOP...... 1.79 SCOP......... No.\6\
h and <760,000 Btu/h, Upflow
Non-ducted.
CRAC, Water-Cooled, <65,000 Btu/ 2.60 SCOP......... 2.50 NSenCOP...... 2.60 SCOP......... No.\4\
h, Downflow.
CRAC, Water-Cooled, <65,000 Btu/ N/A............... 2.70 NSenCOP...... N/A............... Yes.\5\
h, Horizontal-flow.
CRAC, Water-Cooled, <65,000 Btu/ 2.49 SCOP......... 2.30 NSenCOP...... 2.49 SCOP......... No.\4\
h, Upflow Ducted.
CRAC, Water-Cooled, <65,000 Btu/ 2.49 SCOP......... 2.25 NSenCOP...... 2.49 SCOP......... No.\4\
h, Upflow Non-ducted.
CRAC, Water-Cooled, >=65,000 and 2.50 SCOP......... 2.40 NSenCOP...... 2.50 SCOP......... No.\4\
<240,000 Btu/h, Downflow.
CRAC, Water-Cooled, >=65,000 and N/A............... 2.60 NSenCOP...... N/A............... Yes.\5\
<240,000 Btu/h, Horizontal-flow.
CRAC, Water-Cooled, >=65,000 and 2.39 SCOP......... 2.20 NSenCOP...... 2.39 SCOP......... No.\4\
<240,000 Btu/h, Upflow Ducted.
CRAC, Water-Cooled, >=65,000 and 2.39 SCOP......... 2.15 NSenCOP...... 2.39 SCOP......... No.\4\
<240,000 Btu/h, Upflow Non-
ducted.
CRAC, Water-Cooled, >=240,000 2.40 SCOP......... 2.25 NSenCOP...... 2.40 SCOP......... No.\4\
Btu/h and <760,000 Btu/h,
Downflow.
CRAC, Water-Cooled, >=240,000 N/A............... 2.45 NSenCOP...... N/A............... Yes.\5\
Btu/h and <760,000 Btu/h,
Horizontal-flow.
CRAC, Water-Cooled, >=240,000 2.29 SCOP......... 2.10 NSenCOP...... 2.29 SCOP......... No.\4\
Btu/h and <760,000 Btu/h,
Upflow Ducted.
CRAC, Water-Cooled, >=240,000 2.29 SCOP......... 2.05 NSenCOP...... 2.29 SCOP......... No.\4\
Btu/h and <760,000 Btu/h,
Upflow Non-ducted.
CRAC, Water-Cooled with fluid 2.55 SCOP......... 2.45 NSenCOP...... 2.55 SCOP......... No.\4\
economizer, <65,000 Btu/h,
Downflow.
CRAC, Water-Cooled with fluid N/A............... 2.60 NSenCOP...... N/A............... Yes.\5\
economizer, <65,000 Btu/h,
Horizontal-flow.
CRAC, Water-Cooled with fluid 2.44 SCOP......... 2.25 NSenCOP...... 2.44 SCOP......... No.\4\
economizer, <65,000 Btu/h,
Upflow Ducted.
CRAC, Water-Cooled with fluid 2.44 SCOP......... 2.20 NSenCOP...... 2.44 SCOP......... No.\4\
economizer, <65,000 Btu/h,
Upflow Non-ducted.
CRAC, Water-Cooled with fluid 2.45 SCOP......... 2.35 NSenCOP...... 2.45 SCOP......... No.\4\
economizer, >=65,000 and
<240,000 Btu/h, Downflow.
CRAC, Water-Cooled with fluid N/A............... 2.55 NSenCOP...... N/A............... Yes.\5\
economizer, >=65,000 and
<240,000 Btu/h, Horizontal-flow.
CRAC, Water-Cooled with fluid 2.34 SCOP......... 2.15 NSenCOP...... 2.34 SCOP......... No.\4\
economizer, >=65,000 and
<240,000 Btu/h, Upflow Ducted.
CRAC, Water-Cooled with fluid 2.34 SCOP......... 2.10 NSenCOP...... 2.34 SCOP......... No.\4\
economizer, >=65,000 and
<240,000 Btu/h, Upflow Non-
ducted.
CRAC, Water-Cooled with fluid 2.35 SCOP......... 2.20 NSenCOP...... 2.35 SCOP......... No.\4\
economizer, >=240,000 Btu/h and
<760,000 Btu/h, Downflow.
CRAC, Water-Cooled with fluid N/A............... 2.40 NSenCOP...... N/A............... Yes.\5\
economizer, >=240,000 Btu/h and
<760,000 Btu/h, Horizontal-flow.
[[Page 48012]]
CRAC, Water-Cooled with fluid 2.24 SCOP......... 2.05 NSenCOP...... 2.24 SCOP......... No.\4\
economizer, >=240,000 Btu/h and
<760,000 Btu/h, Upflow Ducted.
CRAC, Water-Cooled with fluid 2.24 SCOP......... 2.00 NSenCOP...... 2.24 SCOP......... No.\4\
economizer, >=240,000 Btu/h and
<760,000 Btu/h, Upflow Non-
ducted.
CRAC, Glycol-Cooled, <65,000 Btu/ 2.50 SCOP......... 2.30 NSenCOP...... 2.50 SCOP......... No.\4\
h, Downflow.
CRAC, Glycol-Cooled, <65,000 Btu/ N/A............... 2.40 NSenCOP...... N/A............... Yes.\5\
h, Horizontal-flow.
CRAC, Glycol-Cooled, <65,000 Btu/ 2.39 SCOP......... 2.10 NSenCOP...... 2.39 SCOP......... No.\4\
h, Upflow Ducted.
CRAC, Glycol-Cooled, <65,000 Btu/ 2.39 SCOP......... 2.00 NSenCOP...... 2.39 SCOP......... No.\4\
h, Upflow Non-ducted.
CRAC, Glycol-Cooled, >=65,000 2.15 SCOP......... 2.05 NSenCOP...... 2.15 SCOP......... No.\4\
and <240,000 Btu/h, Downflow.
CRAC, Glycol-Cooled, >=65,000 N/A............... 2.15 NSenCOP...... N/A............... Yes.\5\
and <240,000 Btu/h, Horizontal-
flow.
CRAC, Glycol-Cooled, >=65,000 2.04 SCOP......... 1.85 NSenCOP...... 2.04 SCOP......... No.\4\
and <240,000 Btu/h, Upflow
Ducted.
CRAC, Glycol-Cooled, >=65,000 2.04 SCOP......... 1.85 NSenCOP...... 2.04 SCOP......... Yes.
and <240,000 Btu/h, Upflow Non-
ducted.
CRAC, Glycol-Cooled, >=240,000 2.10 SCOP......... 1.95 NSenCOP...... 2.10 SCOP......... No.\4\
Btu/h and <760,000 Btu/h,
Downflow.
CRAC, Glycol-Cooled, >=240,000 N/A............... 2.10 NSenCOP...... N/A............... Yes.\5\
Btu/h and <760,000 Btu/h,
Horizontal-flow.
CRAC, Glycol-Cooled, >=240,000 1.99 SCOP......... 1.80 NSenCOP...... 1.99 SCOP......... No.\4\
Btu/h and <760,000 Btu/h,
Upflow Ducted.
CRAC, Glycol-Cooled, >=240,000 1.99 SCOP......... 1.75 NSenCOP...... 1.99 SCOP......... Yes.
Btu/h and <760,000 Btu/h,
Upflow Non-ducted.
CRAC, Glycol-Cooled with fluid 2.45 SCOP......... 2.25 NSenCOP...... 2.45 SCOP......... No.\4\
economizer, <65,000 Btu/h,
Downflow.
CRAC, Glycol-Cooled with fluid N/A............... 2.35 NSenCOP...... N/A............... Yes.\5\
economizer, <65,000 Btu/h,
Horizontal-flow.
CRAC, Glycol-Cooled with fluid 2.34 SCOP......... 2.10 NSenCOP...... 2.34 SCOP......... No.\4\
economizer, <65,000 Btu/h,
Upflow Ducted.
CRAC, Glycol-Cooled with fluid 2.34 SCOP......... 2.00 NSenCOP...... 2.34 SCOP......... Yes.
economizer, <65,000 Btu/h,
Upflow Non-ducted.
CRAC, Glycol-Cooled with fluid 2.10 SCOP......... 1.95 NSenCOP...... 2.10 SCOP......... No.\4\
economizer, >=65,000 and
<240,000 Btu/h, Downflow.
CRAC, Glycol-Cooled with fluid N/A............... 2.10 NSenCOP...... N/A............... Yes.\5\
economizer, >=65,000 and
<240,000 Btu/h, Horizontal-flow.
CRAC, Glycol-Cooled with fluid 1.99 SCOP......... 1.80 NSenCOP...... 1.99 SCOP......... No.\4\
economizer, >=65,000 and
<240,000 Btu/h, Upflow Ducted.
CRAC, Glycol-Cooled with fluid 1.99 SCOP......... 1.75 NSenCOP...... 1.99 SCOP......... Yes.
economizer, >=65,000 and
<240,000 Btu/h, Upflow Non-
ducted.
CRAC, Glycol-Cooled with fluid 2.05 SCOP......... 1.90 NSenCOP...... 2.05 SCOP......... No.\4\
economizer, >=240,000 Btu/h and
<760,000 Btu/h, Downflow.
CRAC, Glycol-Cooled with fluid N/A............... 2.10 NSenCOP...... N/A............... Yes.\5\
economizer, >=240,000 Btu/h and
<760,000 Btu/h, Horizontal-flow.
CRAC, Glycol-Cooled with fluid 1.94 SCOP......... 1.80 NSenCOP...... 1.94 SCOP......... No.\4\
economizer, >=240,000 Btu/h and
<760,000 Btu/h, Upflow Ducted.
CRAC, Glycol-Cooled with fluid 1.94 SCOP......... 1.70 NSenCOP...... 1.94 SCOP......... Yes.
economizer, >=240,000 Btu/h and
<760,000 Btu/h, Upflow Non-
ducted.
----------------------------------------------------------------------------------------------------------------
Electrically-Operated Direct Expansion (DX)-Dedicated Outdoor Air System Units, Single-Package and Remote
Condenser
----------------------------------------------------------------------------------------------------------------
DOAS, Air-Cooled, without energy N/A............... 4.0 ISMRE......... N/A............... Yes.
recovery.
DOAS, Air-Cooled, with energy N/A............... 5.2 ISMRE......... N/A............... Yes.
recovery.
DOAS, Air-Source heat pumps, N/A............... 4.0 ISMRE, 2.7 N/A............... Yes.\7\
without energy recovery. ISCOP.
DOAS, Air-Source heat pumps, N/A............... 5.2 ISMRE, 3.3 N/A............... Yes.\7\
with energy recovery. ISCOP.
[[Page 48013]]
DOAS, Water-cooled: Cooling N/A............... 4.9 ISMRE......... N/A............... Yes.\7\
tower condenser water, without
energy recovery.
DOAS, Water-cooled: Cooling N/A............... 5.3 ISMRE......... N/A............... Yes.\7\
tower condenser water, with
energy recovery.
DOAS, Water-cooled: Chilled N/A............... 6.0 ISMRE......... N/A............... Yes.\8\
water, without energy recovery.
DOAS, Water-cooled: Chilled N/A............... 6.6 ISMRE......... N/A............... Yes.\9\
water, with energy recovery.
DOAS, Water-source: Ground- N/A............... 4.8 ISMRE, 2.0 N/A............... Yes.\10\
source, closed loop, without ISCOP.
energy recovery.
DOAS, Water-source: Ground- N/A............... 5.2 ISMRE, 3.8 N/A............... Yes.\11\
source, closed loop, with ISCOP.
energy recovery.
DOAS, Water-source: Ground-water N/A............... 5.0 ISMRE, 3.2 N/A............... Yes.
source, without energy recovery. ISCOP.
DOAS, Water-source: Ground-water N/A............... 5.8 ISMRE, 4.0 N/A............... Yes.
source, with energy recovery. ISCOP.
DOAS, Water-source: Water- N/A............... 4.0 ISMRE, 3.5 N/A............... Yes.\7\
source, without energy recovery. ISCOP.
DOAS, Water-source: Water- N/A............... 4.8 ISMRE, 4.8 N/A............... Yes.\7\
source, with energy recovery. ISCOP.
----------------------------------------------------------------------------------------------------------------
\1\ Note that equipment classes specified in ASHRAE Standard 90.1-2016 do not necessarily correspond to the
equipment classes defined in DOE's regulations.
\2\ This table represents values in ASHRAE 90.1-2013 as corrected by various errata sheets issued by ASHRAE.
\3\ For CRACs, ASHRAE Standard 90.1-2016 adopted efficiency levels in terms of NSenCOP based on test procedures
in AHRI 1360-2016, while DOE's current standards are in terms of SCOP based on the test procedures in ANSI/
ASHRAE 127-2007. DOE performed a crosswalk analysis to compare the stringency of the ASHRAE Standard 90.1-2016
efficiency levels with the current Federal standards. See section II.A of this NODA for further discussion on
the crosswalk analysis performed for CRACs.
\4\ The preliminary CRAC crosswalk analysis indicates that the ASHRAE Standard 90.1-2016 level for this class is
less stringent than the current applicable DOE standard.
\5\ Horizontal-flow CRACs are identified in ASHRAE Standard 90.1-2016 as a new equipment class, and DOE does not
have any data to indicate the market share of horizontal-flow units. In the absence of data regarding market
share and efficiency distribution, DOE is unable to estimate potential savings for horizontal-flow equipment
classes.
\6\ The preliminary CRAC crosswalk analysis indicates that there is no difference in stringency of efficiency
levels for this class between ASHRAE 90.1-2016 and the current Federal standard.
\7\ DOE did not conduct an energy use analysis on this DOAS equipment class, as it is one of six equipment
classes for which the combined market share is estimated to be approximately 5 percent, and as such, standards
would result in minimal national energy savings.
\8\ DOE evaluated as a single class water-cooled, chilled water DOAS without energy recovery product class and
water-cooled, cooling tower condenser water DOAS without energy recovery product class. See section III.A.2
for more details.
\9\ DOE evaluated as a single class water-cooled, chilled water DOAS with energy recovery product class and
water-cooled, cooling tower condenser water DOAS with energy recovery product class. See section III.A.2 for
more details.
\10\ DOE evaluated as a single class water-source: Ground-source DOAS without energy recovery product class and
water-source: Water-source DOAS without energy recovery product class. See section III.A.2 for more details.
\11\ DOE evaluated as a single class water-source: Ground-source DOAS with energy recovery product class and
water-source: Water-source DOAS with energy recovery product class. See section III.A.2 for more details.
A. Computer Room Air Conditioners
DOE currently prescribes energy conservation standards for 30
equipment classes of CRACs at 10 CFR 431.97. The current CRAC equipment
classes are differentiated by condensing system type (air-cooled,
water-cooled, water-cooled with fluid economizer, glycol-cooled, or
glycol-cooled with fluid economizer), net sensible cooling capacity
(less than 65,000 Btu/h, greater than or equal to 65,000 Btu/h and less
than 240,000 Btu/h, or greater than or equal to 240,000 Btu/h and less
than 760,000 Btu/h), and direction of conditioned air over the cooling
coil (upflow or downflow). Federal standards established in 10 CFR
431.97 are specified in terms of SCOP, based on rating conditions in
ANSI/ASHRAE Standard 127-2007, Method of Testing Computer and Data
Processing Room Unitary Air Conditioners (ANSI/ASHRAE 127-2007). 10 CFR
431.96(b)(2).
ASHRAE 90.1-2016 disaggregates the upflow CRAC equipment classes
into upflow ducted and upflow non-ducted equipment classes, and it
establishes different sets of efficiency levels for upflow ducted and
upflow non-ducted equipment classes based on the corresponding rating
conditions specified in AHRI Standard 1360-2016, Performance Rating of
Computer and Data Processing Room Air Conditioners (AHRI 1360-2016).
Section II.A.1 of this document includes a detailed discussion of the
differences in rating conditions between DOE's current test procedure
for CRACs (which references ANSI/ASHRAE 127-2007) and AHRI 1360-2016.
In contrast, DOE currently specifies the same set of standards at 10
CFR 431.97 for all covered upflow CRACs, regardless of ducting
configuration. Additionally, ASHRAE 90.1-2016 includes efficiency
levels for 15 horizontal-flow equipment classes. The equipment in these
15 classes is not currently subject to Federal standards set forth in
10 CFR 431.97.
DOE considered whether there were any increases in stringency in
the ASHRAE 90.1-2016 levels for CRAC classes covered by DOE standards,
thus triggering DOE obligations under EPCA.
[[Page 48014]]
For CRACs, this assessment has been complicated because the current
standards established in 10 CFR 431.97 are specified in terms of SCOP
and based on the rating conditions in ANSI/ASHRAE 127-2007, while the
efficiency levels for CRACs set forth in ASHRAE 90.1-2016 are specified
in terms of NSenCOP and based on rating conditions in AHRI 1360-2016.
While EPCA does not expressly state how DOE is to consider a change to
an ASHRAE efficiency metric, DOE is guided by the criteria established
under EPCA for the evaluation of amendments to the test procedures
referenced in ASHRAE Standard 90.1. For ASHRAE equipment under 42
U.S.C. 6313(a)(6)(A)(i), EPCA directs that if the applicable test
procedure referenced in ASHRAE Standard 90.1 is amended, DOE must amend
the Federal test procedure to be consistent with the amended industry
test procedure, unless DOE makes a determination, supported by clear
and convincing evidence, that to do so would result in a test procedure
that is not reasonably designed to provide results representative of
use during an average use cycle, or is unduly burdensome to conduct.
(42 U.S.C. 6314(a)(4)(B)) In evaluating an update to an industry test
procedure referenced in ASHRAE Standard 90.1, DOE must also consider
any potential impact on the measured energy efficiency as compared to
the current Federal test procedure and in the context of the current
Federal standard. (42 U.S.C. 6314(a)(4)(C) and 42 U.S.C. 6293(e))
As discussed in section II.A.1 of this document, the rating
conditions in AHRI 1360-2016 differ from those specified in ANSI/ASHRAE
127-2007 for most upflow and downflow CRAC equipment classes. DOE
conducted a crosswalk analysis for the classes affected by rating
condition changes to determine whether the revised ASHRAE 90.1-2016
levels in terms of NSenCOP are more stringent than DOE's current
standards in terms of SCOP.
DOE conducted the crosswalk analysis to determine equivalent
NSenCOP values corresponding to DOE's current SCOP-based CRAC standards
in order to perform the analysis required by EPCA. The crosswalk allows
DOE to determine whether any of the levels specified in the updated
ASHRAE Standard 90.1 are more stringent than the current DOE standards,
and therefore amended for the purpose of the evaluation required by
EPCA. (42 U.S.C. 6313(a)(6)(A)(i)) To the extent that the crosswalk
identifies amended standards (i.e., ASHRAE Standard 90.1 levels more
stringent than the Federal standards), the crosswalk also allows DOE to
conduct an analysis of the energy savings potential of amended
standards, also as required by EPCA. (Id.) Additionally, in order to
make the required determination of whether adoption of a uniform
national standard more stringent than the amended ASHRAE Standard 90.1
level is technologically feasible and economically justified (42 U.S.C.
6313(a)(6)(A)(ii)), DOE must understand the relationship between the
current Federal standard and the corresponding ASHRAE Standard 90.1
efficiency level. Finally, for any standard that DOE does not make more
stringent because the Federal standard is already more stringent than
the ASHRAE Standard 90.1 level and where more-stringent levels are not
justified (under the 6-year-lookback), DOE must express these levels in
terms of the new efficiency metric so as to be consistent with the
relevant industry test procedure (42 U.S.C. 6314(a)(4)).
1. Methodology for Efficiency and Capacity Crosswalk Analyses
a. General
DOE performed a crosswalk analysis to compare the stringency of the
current Federal standards (represented in terms of SCOP based on the
current DOE test procedure) for CRACs to the stringency of the energy
efficiency for this equipment in ASHRAE Standard 90.1-2016 (represented
in terms of NSenCOP based on AHRI 1360-2016). For the crosswalk, DOE
analyzed the CRAC equipment classes in ASHRAE 90.1-2016 that are
currently subject to Federal standards (i.e., all upflow and downflow
classes).\11\ ASHRAE 90.1-2016 includes separate sets of efficiency
levels for upflow ducted and upflow non-ducted CRACs to reflect the
differences in rating conditions for upflow ducted and upflow non-
ducted units in AHRI 1360-2016 (e.g., return air temperature and
external static pressure (ESP)). The Federal test procedure does not
specify different rating conditions for upflow ducted as compared to
upflow non-ducted CRACs, and DOE's current standards set forth in 10
CFR 431.97 do not differentiate between upflow ducted and upflow non-
ducted CRACs. For the purpose of the efficiency crosswalk analysis, DOE
converted the single set of current Federal SCOP standards for all
upflow CRACs to sets of ``crosswalked'' NSenCOP standards for both the
upflow ducted and upflow non-ducted classes established in ASHRAE
Standard 90.1-2016.
---------------------------------------------------------------------------
\11\ ASHRAE Standard 90.1-2016 includes efficiency levels for
horizontal-flow classes of CRAC. DOE does not currently prescribe
standards for horizontal-flow classes, so these classes were not
included in the crosswalk analysis.
---------------------------------------------------------------------------
As explained, the standards for CRACs as updated in ASHRAE Standard
90.1-2016 rely on a different metric (NSenCOP) and test procedure (AHRI
1360-2016) than the metric and test procedure required under the
Federal standards (SCOP and ANSI/ASHRAE 127-2007, respectively). AHRI
1360-2016 and ANSI/ASHRAE 127-2007 specify different rating conditions,
which are listed in Table II.2.\12\
---------------------------------------------------------------------------
\12\ Pursuant to EPCA, DOE is conducting a separate evaluation
of its current test procedure as compared to AHRI 1360-2016 (and the
subsequently released 2017 version of AHRI Standard 1360). (42
U.S.C. 6314(a)(4)(B)).
Table II.2--Differences in Rating Conditions Between DOE's Current Test Procedure and AHRI 1360-2016
--------------------------------------------------------------------------------------------------------------------------------------------------------
--------------------------------------------------------------------------------------------------------------------------------------------------------
Test parameter Affected equipment.... Current DOE test procedure (ANSI/ASHRAE 127-
categories............ 2007)
AHRI 1360-2016
--------------------------------------------------------------------------------------------------------------------------------------------------------
Return air dry-bulb temperature Upflow ducted and 75 [deg]F dry-bulb temperature.
(RAT). downflow.
85 [deg]F dry-bulb temperature.
--------------------------------------------------------------------------------------------------------------------------------------------------------
Entering water temperature (EWT)... Water-cooled.......... 86 [deg]F
83 [deg]F
--------------------------------------------------------------------------------------------------------------------------------------------------------
ESP (varies with NSCC)............. Upflow ducted......... <20 kW................ 0.8 in H2O........... <65 kBtu/h........... 0.3 in H2O.
--------------------------------------------------------------------------------------------
[[Page 48015]]
>=20 kW............... 1.0 in H2O........... >=65 kBtu/h and <240 0.4 in H2O.
kBtu/h.
---------------------------------------------
>=240 kBtu/h and <760 0.5 in H2O.
kBtu/h.
--------------------------------------------------------------------------------------------------------------------------------------------------------
Adder for heat rejection fan and Water-cooled and No added power consumption for heat rejection
pump power (add to total power. glycol-cooled. fan and pump.
5 percent of NSCC for water-cooled CRACs.
consumption).
7.5 percent of NSCC for glycol-cooled CRACs.
--------------------------------------------------------------------------------------------------------------------------------------------------------
In addition to necessitating a crosswalk to compare standards that
use different metrics, the differences in the test procedures required
DOE to crosswalk the capacity limits that provide the boundaries for
the CRAC equipment classes. The capacity values that bound the
equipment classes are in terms of net sensible cooling capacity (NSCC).
NSCC values determined according to AHRI 1360-2016, the test procedure
specified in ASHRAE Standard 90.1-2016, are higher than the NSCC values
determined according to ANSI/ASHRAE 127-2007, the required Federal test
procedure. Because the test procedure in ASHRAE Standard 90.1-2016
results in an increased NSCC value for certain equipment classes,
applying ASHRAE Standard 90.1-2016, as compared to the current Federal
requirement, would result in some CRACs switching classes (i.e., move
into a higher capacity equipment class) if the equipment class
boundaries are not changed. Based on the calculated capacity changes,
approximately 15-20 percent of CRAC models listed in DOE's Compliance
Certification Database for CRACs \13\ would shift into higher capacity
equipment classes as a result of the test procedure changes in AHRI
1360-2016.
---------------------------------------------------------------------------
\13\ DOE's Compliance Certification Database can be found at:
https://www.regulations.doe.gov/certification-data/#q=Product_Group_s%3A*.
---------------------------------------------------------------------------
As the equipment class capacity increases, the stringency of the
both the ASHRAE Standard 90.1 efficiency level and the Federal standard
decreases. As a result, class switching would subject some CRAC models
to an efficiency level under ASHRAE Standard 90.1-2016 that is less
stringent than the standard level that is applicable to that model
under the current Federal requirements. This backsliding would result
in an inappropriate evaluation of ASHRAE Standard 90.1-2016.
To provide for an appropriate comparison and to address potential
backsliding, a capacity crosswalk was conducted to adjust the NSCC
boundaries that separate equipment classes to account for the
difference in measured NSCC values between ASHRAE Standard 90.1-2016
and the current Federal requirements. The capacity crosswalk calculated
increases in the capacity boundaries of affected equipment classes
(i.e., equipment classes with test procedure changes that increase
NSCC) to prevent this equipment class switching issue and avoid
potential backsliding that would occur if capacity boundaries were not
adjusted.
Both the efficiency and capacity crosswalk analyses have a similar
structure and the data for both analyses came from several of the same
sources. The crosswalk analyses were informed by numerous sources,
including public manufacturer literature, manufacturer performance data
obtained through non-disclosure agreements (NDAs), results from DOE's
testing of two CRAC units, and DOE's Compliance Certification Database
for CRACs. DOE analyzed each test procedure change independently and
used the available data to determine an aggregated percentage by which
that change impacted efficiency (SCOP) and/or NSCC. Updated SCOP levels
and NSCC equipment class boundaries were calculated for each class (as
applicable) by combining the percentage changes for every test
procedure change applicable to that class.
The following sub-sections describe the approaches used to analyze
the impacts on the measured efficiency and capacity of each difference
in rating conditions between DOE's current test procedure and AHRI
1360-2016.
b. Increase in Return Air Dry-Bulb Temperature From 75 [deg]F to 85
[deg]F
ANSI/ASHRAE 127-2007, which is referenced by DOE's current test
procedure, specifies a return air dry-bulb temperature (RAT) of 75
[deg]F for testing all CRACs. AHRI 1360-2016 specifies an RAT of 85
[deg]F for upflow ducted and downflow CRACs, but specifies an RAT for
upflow non-ducted units of 75 [deg]F. SCOP and NSCC both increase with
increasing RAT for two reasons. First, a higher RAT increases the
cooling that must be done for the air to approach its dew point
temperature (i.e., the temperature at which water vapor will condense
if there is any additional cooling). Second, a higher RAT will tend to
raise the evaporating temperature of the refrigerant, which in turn
raises the temperature of fin and tube surfaces in contact with the
air--the resulting reduction in the portion of the heat exchanger
surface that is below the air's dew point temperature reduces the
potential for water vapor to condense on these surfaces. This is seen
in product specifications which show that the sensible heat ratio \14\
is consistently higher at a RAT of 85 [deg]F than at 75 [deg]F. Because
SCOP is calculated with NSCC, an increase in the fraction of total
cooling capacity that is sensible cooling rather than latent cooling
also inherently increases SCOP.
---------------------------------------------------------------------------
\14\ ``Sensible heat ratio'' is the ratio of sensible cooling
capacity to the total cooling capacity. The total cooling capacity
includes both sensible cooling capacity (cooling associated with
reduction in temperature) and latent cooling capacity (cooling
associated with dehumidification).
---------------------------------------------------------------------------
To analyze the impacts of increasing RAT for upflow ducted and
downflow CRACs on SCOP and NSCC, DOE gathered data from three separate
sources and aggregated the results for each crosswalk analysis. First,
DOE used product specifications for several CRAC models that provide
SCOP and NSCC ratings for RATs ranging from 75 [deg]F to 95 [deg]F.
Second, DOE analyzed manufacturer performance data obtained under NDAs
that showed the performance impact of individual test condition
changes, including the increase in RAT. Third, DOE used results from
testing two CRAC units: One air-cooled upflow ducted and one air-cooled
downflow unit. DOE
[[Page 48016]]
combined the results of these sources to find the aggregated increases
in SCOP and NSCC due to the increase in RAT. The increase in SCOP due
to the change in RAT was found to be approximately 19 percent, and the
increase in capacity was found to be approximately 22 percent.
c. Decrease in Entering Water Temperature for Water-Cooled CRACs
ANSI/ASHRAE 127-2007, which is referenced by DOE's current test
procedure, specifies an entering water temperature (EWT) of 86 [deg]F
for water-cooled CRACs, while AHRI 1360-2016 specifies an entering
water temperature of 83 [deg]F. A decrease in the EWT for water-cooled
CRACs increases the temperature difference between the water and hot
refrigerant in the condenser coil, thus increasing cooling capacity and
decreasing compressor power. To analyze the impact of this decrease in
EWT on SCOP and NSCC, DOE analyzed manufacturer data obtained through
NDAs and a publicly-available presentation from a major CRAC
manufacturer and calculated an SCOP increase of approximately 2 percent
and an NSCC increase of approximately 1 percent.
d. Changes in External Static Pressure Requirements for Upflow Ducted
CRACs
For upflow ducted CRACs, AHRI 1360-2016 specifies lower ESP
requirements than ANSI/ASHRAE 127-2007, which is referenced in DOE's
current test procedure. The ESP requirements in both industry test
standards vary with NSCC; however, the capacity bins (i.e., capacity
ranges over which each ESP requirement applies) are different in each
test standard. Testing with a lower ESP decreases the indoor fan power
input without a corresponding decrease in cooling capacity, thus
increasing the measured efficiency. Additionally, the reduction in fan
heat entering the indoor air stream that results from lower fan power
also slightly increases NSCC.
To determine the impacts on measured SCOP and NSCC of the changes
in ESP requirements between DOE's current test procedure and AHRI 1360-
2016, DOE aggregated data from its analysis of fan power consumption
changes, manufacturer data obtained through NDAs, and results from DOE
testing. More details on each of these sources are included in the
following paragraphs. The impact of changes in ESP requirements on SCOP
and NSCC was calculated separately for each capacity range specified in
AHRI 1360-2016 (i.e., <65 kBtu/h, 65-240 kBtu/h, and >=240 kBtu/h).
DOE conducted an analysis to estimate the change in fan power
consumption due to the changes in ESP requirements using performance
data and product specifications for 77 upflow CRAC models with
certified SCOP ratings at or near the current applicable SCOP standard
level in DOE's Compliance Certification Database. Using the certified
SCOP and NSCC values, DOE determined each model's total power
consumption for operation at the rating conditions specified in DOE's
current test procedure. DOE then used fan performance data for each
model to estimate the change in indoor fan power that would result from
the lower ESP requirements in AHRI 1360-2016, and modified the total
power consumption for each model by the calculated value. For several
models, detailed fan performance data were not available, so DOE used
fan performance data for comparable air conditioning units with similar
cooling capacity, fan drive, and fan motor horsepower.
DOE also received manufacturer data (obtained through NDAs) showing
the impact on efficiency and NSCC of the change in ESP requirements.
Additionally, DOE conducted tests on an upflow-ducted CRAC at ESPs of 1
in. H2O and 0.4 in. H2O (the applicable ESP
requirements specified in ANSI/ASHRAE 127-2007 and AHRI 1360-2016), and
included the results of those tests in this analysis.
For each of the three capacity ranges for which ESP requirements
are specified in AHRI 1360-2016, Table II.3 shows the approximate
aggregated percentage increases in SCOP and NSCC associated with the
decreased ESP requirements specified in AHRI 1360-2016 for upflow
ducted units.
Table II.3--Percentage Increase in SCOP and NSCC From Decreases in External Static Pressure Requirements for
Upflow Ducted Units Between DOE's Current Test Procedure and AHRI 1360-2016
----------------------------------------------------------------------------------------------------------------
ESP requirements in Approx. Approx.
DOE's current test ESP requirements in average average
Net sensible cooling capacity range procedure (ANSI/ AHRI 1360-2016 (in percentage percentage
(kBtu/h) * ASHRAE 127-2007) (in H2O) increase in increase in
H2O) SCOP NSCC
----------------------------------------------------------------------------------------------------------------
<65................................. 0.8 0.3 7 2
>=65 to <240
>=65 to <68.2 **................ 0.8 0.4 *** 8 *** 2
>=68.2 to <240 **............... 1
>=240 to <760....................... 1 0.5 6 2
----------------------------------------------------------------------------------------------------------------
* These boundaries are consistent with ANSI/ASHRAE 127-2007 and AHRI 1360-2016, and do not reflect the expected
capacity increases for certain equipment classes at the AHRI 1360-2016 test conditions.
** 68.2 kBtu/h is equivalent to 20 kW, which is the capacity value that separates ESP requirements in ANSI/
ASHRAE 127-2007, which is referenced in DOE's current test procedure.
*** This average percentage increase is an average across upflow ducted CRACs with net sensible cooling capacity
>=65 and <240 kBtu/h, including models with capacity <20 kW and >= 20 kW. DOE's Compliance Certification
Database shows that most of the upflow CRACs with a net sensible cooling capacity >=65 kBtu/h and <240 kBtu/h
have a net sensible cooling capacity >=20 kW.
e. Power Adder to Account for Pump and Heat Rejection Fan Power in
NSenCOP Calculation for Water-Cooled and Glycol-Cooled CRACs
Energy consumption for heat rejection components for air-cooled
CRACs (i.e., condenser fan motor(s)) is measured in the industry test
standards for CRACs; however, energy consumption for heat rejection
components for water-cooled and glycol-cooled CRACs is not measured
because these components (i.e., water/glycol pump, dry cooler/cooling
tower fan(s)) are not considered to be part of the CRAC unit. ANSI/
ASHRAE 127-2007, which is referenced in DOE's current test procedure,
does not include any factor in the calculation of SCOP to account for
the power consumption of heat rejection components for water-cooled and
[[Page 48017]]
glycol-cooled CRACs. In contrast, AHRI 1360-2016 specifies to increase
the measured total power input for CRACs to account for the power
consumption of fluid pumps and heat rejection fans. Specifically, Notes
5 and 6 to Table 2 of AHRI 1360-2016 specify to add a percentage of the
measured net sensible cooling capacity (5 percent for water-cooled
CRACs and 7.5 percent for glycol-cooled CRACs) in kW to the total power
input used to calculate NSenCOP. DOE calculated the impact of these
additions on SCOP using Equation 1:
[GRAPHIC] [TIFF OMITTED] TP11SE19.000
Where, [chi] is equal to 5 percent for water-cooled CRACs and 7.5
percent for glycol-cooled CRACs, and SCOP1 is the SCOP value
adjusted for the energy consumption of heat rejection pumps and fans.
f. Calculating Overall Changes in Measured Efficiency and Capacity From
Test Procedure Changes
Different combinations of the test procedure changes between DOE's
current test procedure and AHRI 1360-2016 affect each of the CRAC
equipment classes considered in the crosswalk analyses. To combine the
impact on SCOP of the changes to rating conditions (i.e., increase in
RAT, decrease in condenser EWT for water-cooled units, and decrease of
the ESP requirements for upflow ducted units), DOE multiplied together
the calculated adjustment factors representing the measurement changes
corresponding to each individual rating condition change, as
applicable, as shown in Equation 2. These adjustment factors are equal
to 100 percent plus the calculated percent change in measured
efficiency.
To account for the impact of the adder for heat rejection pump and
fan power for water-cooled and glycol-cooled units, DOE used Equation
3. Hence, DOE determined crosswalked NSenCOP levels corresponding to
the current Federal SCOP standards for each CRAC equipment class using
the following two equations.
[GRAPHIC] [TIFF OMITTED] TP11SE19.001
In these equations, NSenCOP1 refers to a partially-
crosswalked NSenCOP level that incorporates the impacts of changes in
RAT, condenser EWT, and indoor fan ESP (as applicable), but not the
impact of adding the heat rejection pump and fan power;
[chi]1, [chi]2, and [chi]3 represent
the percentage change in SCOP due to changes in RAT, condenser EWT, and
indoor fan ESP requirements, respectively; and [chi]4 is
equal to 5 percent for water-cooled equipment classes and 7.5 percent
for glycol-cooled equipment classes. For air-cooled classes,[chi]
4 is equal to 0 percent; therefore, for these classes,
NSenCOP is equal to NSenCOP1.
To combine the impact on NSCC of the changes to rating conditions,
DOE used a methodology similar to that used for determining the impact
on SCOP. To determine adjusted NSCC equipment class boundaries, DOE
multiplied together the calculated adjustment factors representing the
measurement changes corresponding to each individual rating condition
change, as applicable, as shown in Equation 4. These adjustment factors
are equal to 100 percent plus the calculated percent change in measured
NSCC. In this equation, Boundary refers to the original NSCC boundaries
(i.e., 65,000 Btu/h, 240,000 Btu/h, or 760,000 Btu/h as determined
according to ANSI/ASHRAE 127-2007), Boundary1 refers to the
updated NSCC boundaries as determined according to AHRI 1360-2016, and
y1, y2, and y3 represent the percentage changes in NSCC due to changes
in RAT, condenser EWT, and indoor fan ESP requirements, respectively.
[GRAPHIC] [TIFF OMITTED] TP11SE19.002
In November 2018, ASHRAE published the Second Public Review Draft
of Addendum `be' to ASHRAE 90.1-2016 (``the second public review
draft;'' https://www.ashrae.org/news/esociety/public-reviews-november-2018), which includes adjusted equipment class capacity boundaries for
only upflow-ducted and downflow equipment classes.\15\ The adjusted
class boundaries for these categories in the second public review draft
are <80,000 Btu/h, >=80,000 Btu/h and <295,000 Btu/h, and >=295,000
Btu/h. The capacity boundaries of upflow non-ducted classes were left
unchanged at 65,000 Btu/h and 240,000 Btu/h. DOE's capacity crosswalk
analysis indicates that the primary driver for increasing NSCC is
increasing RAT. The increases in RAT in AHRI 1360-2016, as compared to
ANSI/ASHRAE 127-2007, only apply to upflow ducted and downflow
equipment classes. Based on
[[Page 48018]]
the analysis performed for this document, DOE found that all the
equipment class boundaries in the second public review draft, which are
in multiples of 5,000 Btu/h, are within 1.4 percent of the boundaries
calculated under the methodology used to develop DOE's capacity
crosswalk. As such, to more closely align DOE's analysis with ASHRAE
Standard 90.1 (and the ASHRAE proceedings), DOE has used the equipment
class boundaries in the second public review draft as the preliminary
adjusted boundaries for the crosswalk analysis. Use of the equipment
class boundaries from the second public review draft allows for an
appropriate comparison between the energy efficiency levels and
equipment classes specified in ASHRAE Standard 90.1 and those in the
current DOE standards, while addressing the backsliding potential
discussed previously.
---------------------------------------------------------------------------
\15\ In May 2019, ASHRAE published the Third Public Review Draft
of Addendum `be' to ASHRAE 90.1-2016, which includes only minor
changes to column labels in the CRAC efficiency tables proposed in
the second public review draft.
---------------------------------------------------------------------------
ASHRAE 90.1-2016 does not include an upper capacity limit for
coverage of CRACs; therefore, the second public review draft does not
include an adjusted upper capacity limit. DOE's current standards only
cover CRACs with an NSCC less than 760,000 Btu/h.\16\ 10 CFR 431.97(e).
(See also 42 U.S.C. 6311(8)(D)) In order to account for all equipment
currently subject to the Federal standards, DOE adjusted the 760,000
Btu/h equipment class boundary for certain equipment classes as part of
its capacity crosswalk analysis. This adjustment to the upper boundary
of the equipment classes applies only for downflow and upflow-ducted
classes (the classes for which the RAT increase applies). Consistent
with the adjustments made by ASHRAE in the second public review draft,
DOE averaged the cross-walked capacity results across the affected
equipment classes, and rounded to the nearest 5,000 Btu/h. Following
this approach, DOE has used 930,000 Btu/h as the adjusted upper
capacity limit for downflow and upflow-ducted CRACs in the analysis
presented in this notice. The 930,000 Btu/h upper capacity limit (as
measured per AHRI 1360-2016) used in the crosswalk analysis is
equivalent to the 760,000 Btu/h upper capacity limit (as measured per
ANSI/ASHRAE 127-2007) established in the current DOE standards.
---------------------------------------------------------------------------
\16\ In initially establishing standards CRACs, DOE noted that
the energy efficiency levels from ASHRAE Standard 90.1 adopted as
the Federal standards were based on ANSI/ASHRAE 127-2007. 77 FR
28928, 28945 (May 16, 2012). This includes the relevant capacity
values.
---------------------------------------------------------------------------
2. Crosswalk Results
The ``crosswalked'' DOE efficiency levels (in terms of NSenCOP) and
adjusted equipment class capacity boundaries were then compared with
the NSenCOP efficiency levels and capacity boundaries specified in
ASHRAE Standard 90.1-2016 to determine whether the ASHRAE Standard
90.1-2016 requirements are more stringent than current Federal
standards. Table II.4 presents the preliminary results for the
crosswalk analysis (see section II.A.1 of this document for detailed
discussion of the methodology for the crosswalk analysis). The last
column in the table, labeled ``Crosswalk Comparison,'' indicates
whether the ASHRAE Standard 90.1-2016 levels are less stringent,
equivalent to, or more stringent than the current Federal standards,
based on DOE's analysis.
Table II.4--Crosswalk Results
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Cross-walked
Current Test procedure current ASHRAE
Condenser system type Airflow configuration Current NSCC range Federal changes affecting Cross-walked NSCC Federal 90.1-2016 Crosswalk comparison
(kBtu/h) standard efficiency * range (kBtu/h) standard NSenCOP
(SCOP) (NSenCOP) level
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Air-cooled....................... Downflow................. <65................... 2.20 Return air dry-bulb <80................... 2.62 2.30 Less Stringent.
Air-cooled....................... Downflow................. >=65 and <240......... 2.10 temperature. >=80 and <295......... 2.50 2.20 Less Stringent.
Air-cooled....................... Downflow................. >=240 and <760........ 1.90 >=295 and <930........ 2.26 2.00 Less Stringent.
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Water-cooled..................... Downflow................. <65................... 2.60 Return air dry-bulb <80................... 2.73 2.50 Less Stringent.
Water-cooled..................... Downflow................. >=65 and <240......... 2.50 temperature. >=80 and <295......... 2.63 2.40 Less Stringent.
Water-cooled..................... Downflow................. >=240 and <760........ 2.40 Condenser entering >=295 and <930........ 2.54 2.25 Less Stringent.
Water-cooled with fluid Downflow................. <65................... 2.55 water temperature. <80................... 2.68 2.45 Less Stringent.
economizer.
Water-cooled with fluid Downflow................. >=65 and <240......... 2.45 Add allowance for >=80 and <295......... 2.59 2.35 Less Stringent.
economizer. heat rejection
components to total
power input.
Water-cooled with fluid Downflow................. >=240 and <760........ 2.35 >=295 and <930........ 2.50 2.20 Less Stringent.
economizer.
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Glycol-cooled.................... Downflow................. <65................... 2.50 Add allowance for <80................... 2.43 2.30 Less Stringent.
Glycol-cooled.................... Downflow................. >=65 and <240......... 2.15 heat rejection >=80 and <295......... 2.15 2.05 Less Stringent.
Glycol-cooled.................... Downflow................. >=240 and <760........ 2.10 components to total >=295 and <930........ 2.11 1.95 Less Stringent.
Glycol-cooled with fluid Downflow................. <65................... 2.45 power input. <80................... 2.39 2.25 Less Stringent.
economizer.
Glycol-cooled with fluid Downflow................. >=65 and <240......... 2.10 >=80 and <295......... 2.11 1.95 Less Stringent.
economizer.
Glycol-cooled with fluid Downflow................. >=240 and <760........ 2.05 >=295 and <930........ 2.06 1.90 Less Stringent.
economizer.
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Air-cooled....................... Upflow Ducted............ <65................... 2.09 Return air dry-bulb <80................... 2.65 2.10 Less Stringent.
Air-cooled....................... Upflow Ducted............ >=65 and <240......... 1.99 temperature. >=80 and <295......... 2.55 2.05 Less Stringent.
Air-cooled....................... Upflow Ducted............ >=240 and <760........ 1.79 ESP requirements.... >=295 and <930........ 2.26 1.85 Less Stringent.
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Water-cooled..................... Upflow Ducted............ <65................... 2.49 Return air dry-bulb <80................... 2.77 2.30 Less Stringent.
Water-cooled..................... Upflow Ducted............ >=65 and <240......... 2.39 temperature. >=80 and <295......... 2.70 2.20 Less Stringent.
Water-cooled..................... Upflow Ducted............ >=240 and <760........ 2.29 Condenser entering >=295 and <930........ 2.56 2.10 Less Stringent.
Water-cooled with fluid Upflow Ducted............ <65................... 2.44 water temperature. <80................... 2.72 2.25 Less Stringent.
economizer. ESP requirements....
[[Page 48019]]
Water-cooled with fluid Upflow Ducted............ >=65 and <240......... 2.34 Add allowance for >=80 and <295......... 2.65 2.15 Less Stringent.
economizer. Upflow Ducted............ >=240 and <760........ 2.24 heat rejection >=295 and <930........ 2.51 2.05 Less Stringent.
Water-cooled with fluid components to total
economizer. power input.
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Glycol-cooled.................... Upflow Ducted............ <65................... 2.39 Return air dry-bulb <80................... 2.47 2.10 Less Stringent.
Glycol-cooled.................... Upflow Ducted............ >=65 and <240......... 2.04 temperature. >=80 and <295......... 2.19 1.85 Less Stringent.
Glycol-cooled.................... Upflow Ducted............ >=240 and <760........ 1.99 ESP requirements.... >=295 and <930........ 2.11 1.80 Less Stringent.
Glycol-cooled with fluid Upflow Ducted............ <65................... 2.34 Add allowance for <80................... 2.43 2.10 Less Stringent.
economizer. Upflow Ducted............ >=65 and <240......... 1.99 heat rejection >=80 and <295......... 2.14 1.80 Less Stringent.
Glycol-cooled with fluid components to total
economizer. power input.
Glycol-cooled with fluid Upflow Ducted............ >=240 and <760........ 1.94 >=295 and <930........ 2.07 1.80 Less Stringent.
economizer.
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Air-cooled....................... Upflow Non-Ducted........ <65................... 2.09 No changes.......... <65................... 2.09 2.09 Equivalent.
Air-cooled....................... Upflow Non-Ducted........ >=65 and <240......... 1.99 >=65 and <240......... 1.99 1.99 Equivalent.
Air-cooled....................... Upflow Non-Ducted........ >=240 and <760........ 1.79 >=240 and <760........ 1.79 1.79 Equivalent.
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Water-cooled..................... Upflow Non-Ducted........ <65................... 2.49 Condenser entering <65................... 2.25 2.25 Less Stringent.
Water-cooled..................... Upflow Non-Ducted........ >=65 and <240......... 2.39 water temperature. >=65 and <240......... 2.17 2.15 Less Stringent.
Water-cooled..................... Upflow Non-Ducted........ >=240 and <760........ 2.29 >=240 and <760........ 2.09 2.05 Less Stringent.
Water-cooled with fluid Upflow Non-Ducted........ <65................... 2.44 Add allowance for <65................... 2.21 2.20 Less Stringent.
economizer. Upflow Non-Ducted........ >=65 and <240......... 2.34 heat rejection >=65 and <240......... 2.13 2.10 Less Stringent.
Water-cooled with fluid components to total
economizer. power input.
Water-cooled with fluid Upflow Non-Ducted........ >=240 and <760........ 2.24 >=240 and <760........ 2.05 2.00 Less Stringent.
economizer.
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Glycol-cooled.................... Upflow Non-Ducted........ <65................... 2.39 Add allowance for <65................... 2.03 2.00 Less Stringent.
Glycol-cooled.................... Upflow Non-Ducted........ >=65 and <240......... 2.04 heat rejection >=65 and <240......... 1.77 1.85 More Stringent.
Glycol-cooled.................... Upflow Non-Ducted........ >=240 and <760........ 1.99 components to total >=240 and <760........ 1.73 1.75 More Stringent.
power input.
Glycol-cooled with fluid Upflow Non-Ducted........ <65................... 2.34 <65................... 1.99 2.00 More Stringent.
economizer.
Glycol-cooled with fluid Upflow Non-Ducted........ >=65 and <240......... 1.99 >=65 and <240......... 1.73 1.75 More Stringent.
economizer.
Glycol-cooled with fluid Upflow Non-Ducted........ >=240 and <760........ 1.94 >=240 and <760........ 1.69 1.70 More Stringent.
economizer.
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
* Refer to Table II.3 of this document for specific changes in rating conditions.
CRAC Issue 2: DOE requests comment on the methodology and results
for the crosswalk analysis.
As indicated by the crosswalk, a number of the standard levels
established for CRACs in ASHRAE 90.1-2016 are less stringent than the
current Federal standards. DOE is aware that ASHRAE is currently
working on the next version of ASHRAE Standard 90.1, which is expected
to be issued sometime in 2019. (Generally, ASHRAE updates the standard
on a three-year cycle.) A preliminary review of the second public
review draft of Addendum `be' to ASHRAE 90.1-2016 indicates that a
number of the draft efficiency levels for CRACs would be more efficient
than the current Federal standards. The draft addendum also would
update capacity bin boundaries for upflow ducted and downflow CRAC
equipment classes, to reflect the increase in NSCC that results from
changes in the test procedure and metric adopted in the updates under
ASHRAE Standard 90.1-2016 (as discussed in previous sections).
DOE continues to monitor the efforts of ASHRAE in development of
the consensus industry standard, and upon publication of the updated
ASHRAE Standard 90.1, DOE will conduct an analysis as required under
EPCA of any updated efficiency levels for CRACs.
3. CRAC Standards Amended Under ASHRAE Standard 90.1
As discussed, DOE has analyzed the updated CRAC efficiency levels
in ASHRAE 90.1-2016 for the purpose of 42 U.S.C. 6313(a)(6)(A). DOE
identified five equipment classes for which the ASHRAE 90.1-2016
efficiency levels are more stringent than current DOE efficiency levels
(expressed in NSenCOP, see the crosswalk results presented in section
II.A.2 of this document), and 15 classes of CRACs for which standards
are specified in ASHRAE Standard 90.1-2016 that are not currently
subject to DOE's standards (i.e., horizontal-flow). DOE has conducted
an energy savings analysis, presented in section III of this document,
for the five CRAC classes that currently have DOE standards and that
DOE identified as having more stringent standards under ASHRAE 90.1-
2016. Regarding the energy efficiency levels for the horizontal-flow
equipment classes, DOE was unable to perform an energy savings
potential for
[[Page 48020]]
those 15 equipment classes, because DOE lacked the necessary market
share data to disaggregate shipments for horizontal-flow units from
total shipments for the entire CRAC market. Based on information
received in response to this document or otherwise identified, DOE may
consider disaggregating horizontal-flow classes in the NOPR and
analyzing them separately.
DOE notes that ceiling-mounted CRACs, both ducted and non-ducted,
are covered equipment under the definition of ``computer room air
conditioner'' established at 10 CFR 431.92. The current definition of
``computer room air conditioner'' makes no distinction based on the
mounting (floor versus ceiling, for example), airflow direction, or
whether the unit installation requires supply air ductwork.\17\
Additionally, the currently applicable test procedure in 10 CFR 431.96
(i.e., ANSI/ASHRAE 127-2007) is not specific as to mounting or airflow
direction (e.g., upflow, downflow, horizontal) and provides procedures
for both ducted systems (ANSI/ASHRAE 127-2007 section 5.1.4.5.1) and
non-ducted systems (ANSI/ASHRAE 127-2007 section 5.1.4.5.3). As a
result, ceiling-mounted CRACs are covered equipment and are currently
subjected to testing and rating under the DOE regulations.
---------------------------------------------------------------------------
\17\ ``Computer Room Air Conditioner'' is defined as ``a basic
model of commercial package air-conditioning and heating equipment
(packaged or split) that is: Used in computer rooms, data processing
rooms, or other information technology cooling applications; rated
for sensible coefficient of performance (SCOP) and tested in
accordance with 10 CFR 431.96, and is not a covered consumer product
under 42 U.S.C. 6291(1)-(2) and 6292. A computer room air
conditioner may be provided with, or have as available options, an
integrated humidifier, temperature, and/or humidity control of the
supplied air, and reheating function.'' 10 CFR 431.92
---------------------------------------------------------------------------
DOE specifies minimum efficiency standards for certain equipment
classes of CRACs, specifically for upflow and downflow units. See 10
CFR 431.97. In an October 7, 2015 draft guidance, DOE stated that
because the terms ``upflow'' and ``downflow'' do not apply to ceiling-
mounted units, the current Federal standards are not applicable to
those models that are exclusively ceiling-mounted CRACs.\18\ DOE
requested comment on the October 7, 2015 draft guidance. For the
purpose of the analysis presented in this notice, DOE maintains that
ceiling-mounted units are not subject to the current Federal standards
for CRACs.
---------------------------------------------------------------------------
\18\ See, https://www1.eere.energy.gov/buildings/appliance_standards/pdfs/crac_faq_2015-10-07.pdf.
---------------------------------------------------------------------------
The 2016 update to ASHRAE Standard 90.1 does not directly address
ceiling-mounted CRACs, but it specifies equipment classes of: Upflow
ducted, upflow non-ducted, downflow, and horizontal flow. Consistent
with the application of ``upflow'' and ``downflow'' in the draft
guidance, the equipment classes specified in ASHRAE Standard 90.1-2016
do not include ceiling-mounted CRACs. As such, DOE did not include
ceiling-mounted CRACs in the current analysis. DOE is aware that the
second public review draft of Addendum `be' to ASHRAE 90.1-2016
includes minimum efficiency levels for ceiling-mounted CRACs. To the
extent the next amendment to ASHRAE Standard 90.1 includes efficiency
levels for ceiling-mounted CRACs, DOE will evaluate energy efficiency
standards for them to the extent required under EPCA.
B. Dedicated Outdoor Air Systems
DOASes appear to meet the EPCA definition for ``commercial package
air conditioning and heating equipment,'' \19\ and could be considered
as a category of that covered equipment. (42 U.S.C. 6311(8)(A))
However, DOE has tentatively concluded that if DOASes are a category of
``commercial package air conditioning and heating equipment,'' there
are no existing DOE test procedures or energy conservation standards
for that category of commercial package air conditioning and heating
equipment. Specifically, DOE does not believe that DOASes are among the
commercial ``central air conditioners and central air conditioning heat
pumps'' for which EPCA originally established standards (42 U.S.C.
6313(a)(1)-(2),(7)-(9)), and for which the current test procedure and
standards are codified in Table 1 to 10 CFR 431.96 and Tables 1-4 of 10
CFR 431.97, respectively.
---------------------------------------------------------------------------
\19\ Under the statute, ``commercial package air conditioning
and heating equipment'' means air-cooled, water-cooled,
evaporatively-cooled, or water-source (not including ground-water-
source) electrically operated, unitary central air conditioners and
central air conditioning heat pumps for commercial application. (42
U.S.C. 6311(8)(A))
---------------------------------------------------------------------------
DOASes operate similarly to central air conditioners and central
air conditioning heat pumps, in that they provide space conditioning
using a refrigeration cycle consisting of a compressor, condenser,
expansion valve, and evaporator. However, DOASes are designed to
provide 100 percent outdoor air to the conditioned space, while outdoor
air makes up a only a small portion of the total airflow for typical
commercial air conditioners, usually less than 50 percent. When
operating in humid conditions, the dehumidification load is a much
larger percentage of total cooling load for a DOAS than for a typical
commercial air conditioner. Additionally, compared to a typical
commercial air conditioner, the amount of total cooling (both sensible
and latent) is much greater per pound of air for a DOAS at design
conditions (i.e., the warmest/most humid expected summer conditions),
and a DOAS is designed to accommodate greater variation in entering air
temperature and humidity. DOASes are typically installed in addition to
a primary cooling system (e.g., CUAC, VRF, chilled water system, water-
source heat pumps)--the DOAS conditions the outdoor ventilation air,
while the primary system provides cooling to balance building shell and
interior loads and solar heat gain.
ASHRAE Standard 90.1-2016 created 14 separate equipment classes for
direct expansion-DOAS units that are single-package and remote
condenser (referred to generally as DOAS), as shown in Table II.1 of
this document, and set minimum efficiency levels using the integrated
seasonal moisture removal efficiency (ISMRE) metric for all DOAS
classes in dehumidification mode, as well as the integrated seasonal
coefficient of performance (ISCOP) metric for air-source heat pump and
water-source heat pump DOAS classes in heating mode.
If ASHRAE Standard 90.1 is amended with respect to the standard
levels or design requirements applicable under that standard to any
small, large, or very large commercial package air conditioning and
heating equipment, DOE must publish an analysis of the energy savings
potential of amended energy efficiency standards, and adopt uniform
national standards for that equipment as required under EPCA. (42
U.S.C. 6313(a)(6)(A))
The 14 separate DOAS classes created by ASHRAE Standard 90.1-2016
(see Table II.1) are differentiated by condensing type (air-cooled,
air-source heat pump, water-cooled, and water-source heat pump). The
water-cooled condensing type is further divided by cooling tower
condenser water and chilled water. The water-source heat pump
condensing type is further separated by ground-source closed loop,
ground-water-source, and water-source. Additionally, all equipment
classes are separated into those without energy recovery and those with
energy recovery. On July 25, 2017, DOE published an RFI in response to
relevant updates to the test procedures referenced in ASHRAE Standard
90.1-
[[Page 48021]]
2016. 82 FR 34427 (July 2017 ASHRAE TP RFI). As noted in the ASHRAE TP
RFI, the EPCA definition for ``commercial package air conditioning and
heating equipment'' does not include ground-water-source equipment. 82
FR 34427, 34438 (July 25, 2017). (See also, 42 U.S.C. 6311(8)(A)) As
such, DOE is only considering the remaining 12 DOAS equipment classes.
DOE considered whether to evaluate separately the two water-cooled
DOAS classes or whether the water-cooled cooling tower condenser water
classes and the water-cooled chilled water classes should be grouped
together and represented as water-cooled DOASes (with classes still
disaggregated by those models with energy recovery and those models
without energy recovery). DOE also considered whether to evaluate
separately the two remaining water-source heat pump classes or whether
the water-source heat pump ground-source closed loop classes and the
water-source heat pump water-source classes should be grouped together
and represented as water-source heat pump DOASes (with classes still
disaggregated by those models with energy recovery and those models
without energy recovery). Based on DOE's review of equipment
specifications of water-cooled and water-source heat pump DOASes and
comments from AHRI on the concurrent test procedure evaluation,\20\ DOE
determined that most water-cooled DOASes use the same equipment for
different applications and that water-source heat pump DOASes use the
same equipment design for different applications. DOE is not aware of
water-cooled DOAS units that are exclusively designed for use with
cooling tower or chilled water. Likewise, DOE is not aware of water-
source heat pump DOAS units that are exclusively designed for use with
water-source or ground-source closed-loop applications. It is also
DOE's understanding that ASHRAE Standard 90.1 efficiency levels are
different across comparable classes within the water-cooled condensing
type (e.g., comparing energy recovery classes to energy recovery
classes) and across comparable classes within the water-source
condensing type because of the different test/application conditions,
as opposed to equipment design differences. For example, when testing a
DOAS to obtain a water-cooled chilled water DOAS rating, a colder
condenser water entering temperature is used than when testing it to
obtain a water-cooled cooling tower DOAS rating, reflecting the
typically cooler temperature of chilled water loops in commercial
buildings, as compared with cooling tower water loops.
---------------------------------------------------------------------------
\20\ See EERE-2017-BT-TP-0018-0011 at p. 17.
---------------------------------------------------------------------------
As a result, DOE combined the water-cooled cooling tower condenser
water classes and the water-cooled chilled water classes and evaluated
water-cooled DOASes as a single set of classes (with classes
disaggregated by those models with energy recovery and those models
without energy recovery) that is subject to a single set of operating
conditions. DOE also combined the water-source heat pump ground-source
closed loop classes and the water-source heat pump water-source classes
and evaluated the water-source heat pump DOASes as a single set of
classes (with classes still disaggregated by those models with energy
recovery and those models without energy recovery) that is subject to a
single set of operating conditions.
This approach is consistent with other commercial package air
conditioning and heating equipment. For example, water-source heat
pumps include application test conditions for water-loop, ground-water,
and ground-loop heat pumps, but DOE only requires that equipment be
rated using the water-loop conditions (see Table 3 to 10 CFR 431.97).
DOE notes that this approach avoids testing under multiple application
conditions for a single equipment design. In addition, even if tested
at different application conditions because the DOAS equipment uses a
single design, it is expected that the relative ranking of equipment
efficiency would be the same.
The current industry test standard for DOASes, ANSI/AHRI Standard
920-2015, ``2015 Standard for Performance Rating of DX-Dedicated
Outdoor Air System Units,'' references ANSI/ASHRAE Standard 198-2013,
``Method of Test for Rating DX-Dedicated Outdoor Air Systems for
Moisture Removal Capacity and Moisture Removal Efficiency'' (ANSI/
ASHRAE 198-2013), as the method of test for DOASes. In the July 2017
ASHRAE TP RFI, DOE also noted that section 2 of ANSI/ASHRAE 198-2013
specifically excludes DOASes with water coils that are supplied by a
chiller located outside of the unit. 82 FR 34427, 33438 (July 25,
2017). However, Table 2 in ANSI/AHRI 920-2015 includes operating
conditions for which a water-cooled condenser is supplied with chilled
water, and ASHRAE 90.1-2016 established standard levels for DOASes that
operate with chilled water as the condenser cooling fluid. Id. As part
of the concurrent test procedure evaluation, AHRI commented that the
industry test standard for DOASes was designed for units that contain
vapor compression cycle based cooling and dehumidification with direct
expansion coils. AHRI stated that direct application of chilled water
coils to cool and dehumidify is outside the scope of the standard as
the energy for cooling is expended at an external source of chilled
water. (EERE-2017-BT-TP-0018-0011 \21\ at p. 18) Carrier commented that
chillers should only be used for cooling coils and not for condenser
heat rejection unless there is heat reclaim, and that this should be
addressed with a building efficiency standard such as ASHRAE Standard
90.1. (EERE-2017-BT-TP-0018-0006 at p. 7) Based on these comments, DOE
did not evaluate DOAS units that use chilled water coils directly for
cooling and dehumidifying.
---------------------------------------------------------------------------
\21\ Docket No. EERE-2017-BT-TP-0018 is available at https://www.regulations.gov/docket?D=EERE-2017-BT-TP-0018.
---------------------------------------------------------------------------
As discussed above, AHRI commented on the concurrent test procedure
evaluation that in almost all cases, a single design is used for water-
cooled equipment used with cooling tower water and chilled water, and
similarly, a single design is used for all of the water-source
applications, adding that for each of these cases, a single set of
water conditions can be used for testing. (EERE-2017-BT-TP-0018-0011 at
p. 17) AHRI recommended as part of the on-going process to update ANSI/
AHRI 920-2015 that the cooling tower condenser water entering
temperature be used for testing and rating all water-cooled DOASes and
that the water-source inlet fluid temperature conditions be used for
testing and rating all water-source heat pump DOASes. Based on this,
DOE evaluated water-cooled DOASes using the cooling tower condenser
water entering temperature conditions specified in Table 2 of ANSI/AHRI
920-2015, and water-source heat pump DOASes using the water-source
(rather than ground-source) inlet fluid temperature conditions
specified in Table 3 of ANSI/AHRI 920-2015. In addition, DOE conducted
the analysis for water-cooled DOASes based on the efficiency levels
established in ASHRAE Standard 90.1-2016 for the water-cooled cooling
tower condenser water equipment classes, and for water-source heat pump
DOASes based on the efficiency levels established in ASHRAE Standard
90.1-2016 for the water-source (rather than ground-source) equipment
classes. This reduces the considered equipment classes to eight.
DOAS Issue 1: DOE requests comment on the approach of evaluating
water-cooled DOASes as a single category (with classes
[[Page 48022]]
still disaggregated by those models with energy recovery and those
models without energy recovery) using the specified cooling tower
condenser water entering temperature conditions, and evaluating
water-source heat pump DOASes as a single category (with classes
still disaggregated by those models with energy recovery and those
models without energy recovery) using the specified water-source
(rather than ground-source) inlet fluid temperature conditions.
Among the eight equipment classes, DOE identified two classes, the
air-cooled dehumidification-only (i.e., no heat pump function) classes
(including both energy recovery and non-energy recovery), as
representing 95-percent of the DOAS market. The remaining five-percent
of the market is split between the remaining four water-cooled and
water-source equipment classes. DOE is not aware of significant market
share of air-source heat pump DOAS. Due to the low market share and
corresponding minimal potential energy savings, DOE did not evaluate
the energy savings potential for these six equipment classes.
Therefore, DOE conducted an analysis of energy savings potential for
only the two air-cooled dehumidification-only equipment classes, which
is described in section III of this document.
As discussed, no DOE test procedures or Federal uniform national
standards exist for DOASes, a category of commercial package air
conditioning and heating equipment. ASHRAE Standard 90.1-2016 includes
a test procedure for DOASes (i.e., ANSI/AHRI Standard 920-2015). DOE
must amend the Federal test procedure to be consistent with the amended
industry test procedure, unless DOE determines that to do so would
result in a test procedure that is not reasonably designed to provide
results representative of use during an average use cycle, or is unduly
burdensome to conduct. (42 U.S.C. 6314(a)(4)(A)-(B))
AHRI is currently revising AHRI 920, and DOE is participating in
that process. DOE may consider updates to the industry test standard
when finalized, including evaluating potential impacts of any test
procedure changes. ASHRAE Standard 90.1-2016 established minimum
efficiency levels for DOASes, based on testing according to ANSI/AHRI
920-2015. Based on DOE's participation in the revision process, DOE
notes that, if adopted, the proposed changes to AHRI 920 may alter the
measured efficiency compared to that under the industry test standard
referenced in ASHRAE 90.1-2016 (i.e., ANSI/AHRI 920-2015). If DOE
adopts the test procedures changes in the revised AHRI 920, DOE may
develop a crosswalk from the efficiency levels in ASHRAE 90.1-2016 to
the levels that would result under the revised AHRI 920 to
appropriately evaluate the ASHRAE Standard 90.1-2016 provisions
regarding DOASes.
DOAS Issue 2: DOE requests comment and data on developing a
potential crosswalk from the efficiency levels in ASHRAE 90.1-2016
based on ANSI/AHRI 920-2015 to efficiency levels based on the
revisions to AHRI 920.
C. Test Procedures
EPCA requires the Secretary to amend the test procedures for ASHRAE
equipment to the latest version generally accepted by industry or the
rating procedures developed or recognized by AHRI or by ASHRAE, as
referenced by ASHRAE/IES Standard 90.1, unless the Secretary determines
by clear and convincing evidence that the latest version of the
industry test procedure does not meet the requirements for test
procedures described in paragraphs (2) and (3) of 42 U.S.C.
6314(a).\22\ (42 U.S.C. 6314(a)(4)(B)) ASHRAE Standard 90.1-2016
updated several of its test procedures for ASHRAE equipment.
Specifically, ASHRAE Standard 90.1-2016 updated to a more recent
industry test standard for CRACs (AHRI 1360-2016) and adopted a test
procedure for DOASes (ANSI/AHRI 920-2015). As stated, DOE is addressing
the statutorily required evaluation of the test procedure updates
separate from the evaluation presented in this document. In the ASHRAE
TP RFI, DOE summarized its review of the updated industry test
procedures, including changes as compared to the existing DOE test
procedures, and requested comments and supporting data regarding
representative and repeatable methods for measuring the energy use of
the equipment. 82 FR 34427 (July 25, 2017).
---------------------------------------------------------------------------
\22\ Specifically, the relevant provisions (42 U.S.C.
6314(a)(2)-(3)) provide that test procedures must be reasonably
designed to produce test results that reflect energy efficiency,
energy use, and estimated operating costs of a type (or class) of
industrial equipment during a representative average use cycle and
must not be unduly burdensome to conduct. Moreover, if the test
procedure is for determining estimated annual operating costs, it
must provide that such costs will be calculated from measurements of
energy use in a representative average-use cycle, and from
representative average unit costs of the energy needed to operate
the equipment during such cycle. The Secretary must provide
information to manufacturers of covered equipment regarding
representative average unit costs of energy.
---------------------------------------------------------------------------
III. Analysis of Standards Amended and Newly Established by ASHRAE
Standard 90.1-2016
As required under 42 U.S.C. 6313(a)(6)(A), for CRAC equipment
classes with ASHRAE standard levels more stringent than the current
Federal standards and DOASes for which ASHRAE established new standard
levels, DOE performed an analysis to determine the energy-savings
potential of amending Federal CRAC standards to the amended ASHRAE
levels and adopting Federal DOAS standard levels as specified in ASHRAE
Standard 90.1-2016.
As discussed, if DOE determines by rule published in the Federal
Register, and supported by clear and convincing evidence, that adoption
of a uniform national standard more stringent than the amended ASHRAE
Standard 90.1 level would result in significant additional conservation
of energy and is technologically feasible and economically justified,
DOE must adopt the more-stringent standard. (42 U.S.C.
6313(a)(6)(A)(ii)(II) and (B)(i)) Therefore, for the CRAC equipment
classes for which the ASHRAE 90.1 levels are more stringent than the
current Federal standards and for DOASes for which ASHRAE established
standards, DOE is also evaluating whether more stringent standards
would meet the specified statutory criteria.
DOE performed an analysis of the potential energy savings at
standard levels more stringent than the amended ASHRAE standards for
CRACs and the established ASHRAE standards for DOASes. DOE's energy
savings analysis is limited to equipment classes for which a market
exists and sufficient data are available.
To determine whether a standard is economically justified, EPCA
requires that DOE determine whether the benefits of the standard exceed
its burdens by considering, to the greatest extent practicable, the
following seven factors:
(1) The economic impact of the standard on manufacturers and
consumers of the equipment subject to the standard;
(2) The savings in operating costs throughout the estimated average
life of the covered equipment in the type (or class) compared to any
increase in the price, initial charges, or maintenance expenses for the
covered products that are likely to result from the standard;
(3) The total projected amount of energy savings likely to result
directly from the standard;
(4) Any lessening of the utility or the performance of the covered
equipment likely to result from the standard;
[[Page 48023]]
(5) The impact of any lessening of competition, as determined in
writing by the Attorney General, that is likely to result from the
standard;
(6) The need for national energy and water conservation; and
(7) Other factors the Secretary of Energy (Secretary) considers
relevant.
(42 U.S.C. 6313(a)(6)(B)(ii)(I)-(VII))
DOE fulfills these and other applicable requirements by conducting
a series of analyses throughout the rulemaking process. Table III.1
shows the individual analyses that are performed to satisfy each of the
requirements within EPCA.
Table III.1--EPCA Requirements and Corresponding DOE Analysis
------------------------------------------------------------------------
EPCA requirement Corresponding DOE analysis
------------------------------------------------------------------------
Significant Energy Savings............. Shipments Analysis
National Impact
Analysis
Energy and Water Use
Determination
Technological Feasibility.............. Market and Technology
Assessment
Screening Analysis
Engineering Analysis
Economic Justification:
1. Economic impact on manufacturers Manufacturer Impact
and consumers. Analysis
Life-Cycle Cost and
Payback Period Analysis
Life-Cycle Cost
Subgroup Analysis
Shipments Analysis
2. Lifetime operating cost savings Markups for Product
compared to increased cost for the Price Determination
product. Energy and Water Use
Determination
Life-Cycle Cost and
Payback Period Analysis
3. Total projected energy savings.. Shipments Analysis
National Impact
Analysis
4. Impact on utility or performance Screening Analysis
Engineering Analysis
5. Impact of any lessening of Manufacturer Impact
competition. Analysis
6. Need for national energy and Shipments Analysis
water conservation. National Impact
Analysis
7. Other factors the Secretary Employment Impact
considers relevant. Analysis
Utility Impact
Analysis
Emissions Analysis
Monetization of
Emission Reductions Benefits
Regulatory Impact
Analysis
------------------------------------------------------------------------
The following discussion provides an overview of the energy savings
analysis conducted for 5 classes of CRACs and 2 classes of DOASes as
defined by ASHRAE Standard 90.1-2016, followed by summary results of
that analysis. Although ASHRAE Standard 90.1-2016 introduced levels for
15 horizontal flow CRAC equipment classes, DOE was unable to estimate
energy savings due to a lack of data (see section III.B.1 for details).
The issues relevant to the energy use analysis are also relevant to
the technical and economic analyses DOE intends to conduct for CRACs
and DOASes as necessary. In addition to the specific issues identified
in the following sections on which DOE requests comment, DOE requests
comment on its overall approach and analyses used to evaluate potential
standard levels for CRACs and DOASes.
For the equipment classes where ASHRAE Standard 90.1-2016
prescribed more-stringent levels, DOE calculated the potential energy
savings to the Nation associated with adopting ASHRAE Standard 90.1-
2016 as the difference between a no-new-standards case projection
(i.e., without amended standards) and the ASHRAE Standard 90.1-2016
standards-case projection (i.e., with adoption of ASHRAE Standard 90.1-
2016 levels). For each higher efficiency level analyzed, DOE also
calculated potential additional energy savings to the Nation as the
difference between the ASHRAE Standard 90.1-2016 standards-case
projection (i.e., with adoption of ASHRAE Standard 90.1-2016 levels)
and a more-stringent standards-case projection (i.e., with more-
stringent amended standards).
The national energy savings (NES) refers to cumulative lifetime
energy savings for equipment purchased in a 30-year period that differs
by equipment (i.e., the compliance date differs by equipment class
(i.e., capacity) depending upon whether DOE is acting under the ASHRAE
trigger or the 6-year-lookback (see 42 U.S.C. 6313(a)(6)(D)). In the
standards case, equipment that is more efficient gradually replaces
less-efficient equipment over time. This affects the calculation of the
potential energy savings, which are a function of the total number of
units in use and their efficiencies. Savings depend on annual shipments
and equipment lifetime. Inputs to the energy savings analysis are
presented in this notice, and details are available in the CRAC/DOAS
NODA and RFI technical support document (TSD) on DOE's website.\23\
---------------------------------------------------------------------------
\23\ The CRAC/DOAS NODA and RFI TSD is available on the web page
for ASHRAE Products at: http://www1.eere.energy.gov/buildings/appliance_standards/commercial/ashrae_products_docs_meeting.html.
---------------------------------------------------------------------------
A. Annual Energy Use
The purpose of the energy use analysis is to assess the energy
savings potential of different equipment efficiencies in the building
types that utilize the equipment. DOE uses the annual energy
consumption and energy-savings potential in the life-cycle cost (LCC)
and payback period (PBP) analyses \24\ to establish the savings in
consumer operating costs at various equipment efficiency levels.
---------------------------------------------------------------------------
\24\ The purpose of the LCC and PBP analyses are to analyze the
effects of potential amended energy conservation standards on
commercial consumers of CRACs and DOASes by determining how a
potential amended standard affects the commercial consumers'
operating expenses (usually decreased) and total installed costs
(usually increased).
---------------------------------------------------------------------------
The Federal standard and higher efficiency levels are expressed in
terms of an efficiency metric or metrics. For each equipment class,
this section describes how DOE developed estimates
[[Page 48024]]
of annual energy consumption at the baseline efficiency level and at
higher levels for each equipment category. These annual unit energy
consumption (UEC) estimates form the basis of the national energy
savings estimates discussed in section III.F of this document. More
detailed discussion is found in the chapter 2 of the CRAC/DOAS NODA and
RFI TSD.
1. Computer Room Air Conditioners
a. Equipment Classes and Analytical Scope
As noted previously in section II.A.3, DOE has conducted an energy
savings analysis for the five CRAC classes that currently have both DOE
standards and more-stringent standards under ASHRAE Standard 90.1. For
horizontal-flow classes, DOE was unable to obtain market data to
disaggregate energy savings potential for these equipment classes.
Based on information received in response to this document or otherwise
identified, DOE may disaggregate horizontal-flow classes in the NOPR
and analyze them separately.
DOE conducted an energy analysis for 15 downflow CRAC equipment
classes as part of the May 2012 final rule. 77 FR 28928, 28954 (May 16,
2012). In the May 2012 final rule, DOE used a modified outside
temperature bin analysis. For each air-cooled equipment class, DOE
calculated fan energy and condensing unit power consumption at each 5
[deg]F outdoor air dry bulb temperature bin. The condensing unit power
in this context included the compressor(s) and condenser fan(s) and/or
pump(s) included as part of the equipment rating. For water-cooled and
glycol-cooled equipment, the May 2012 final rule analysis first
estimated the entering fluid temperature from either an evaporative
cooling tower or a dry cooler for water-cooled and for glycol-cooled
CRAC equipment, respectively, based on binned weather data. Using these
results, DOE then estimated the condensing unit power consumption and
adds to this the estimated supply fan power. The sum of the CRAC
condensing unit power and the CRAC supply fan power is the estimated
average CRAC total power consumption for each temperature bin. Annual
estimates of energy use are developed by multiplying the power
consumption at each temperature bin by the number of hours in that bin
for each climate analyzed. In the May 2012 final rule, DOE then took a
population-weighted average over results for 239 different climate
locations to derive nationally representative CRAC annual energy use
values. DOE assumed energy savings estimates derived for downflow
equipment classes would be representative of upflow equipment. 77 FR
28928, 28954 (May 16, 2012). In this document, DOE is using the results
from the May 2012 final rule as the basis for the energy savings
potential analysis of the five CRAC equipment classes analyzed for this
document.
b. Efficiency Levels
DOE identified the baseline, intermediate, and maximum
technologically feasible (max-tech) efficiency levels for each
equipment class. DOE used the Federal standard and the ASHRAE Standard
90.1-2016 level as baselines. The Federal standard is used as a
baseline when estimating energy savings associated with adopting the
ASHRAE Standard 90.1-2016 level. Savings from higher efficiency levels
are measured relative to the ASHRAE Standard 90.1-2016 baseline. EL 0
refers to the ASHRAE Standard 90.1-2016 level.
To determine the intermediate and max-tech efficiency levels, DOE
created an equipment database composed of CRAC models rated in terms of
SCOP found in DOE's Compliance Certification Database.\25\ Using this
database, DOE created efficiency distribution plots for each equipment
class and identified intermediate efficiency levels that correspond to
efficiencies with a higher frequency of models available on the market.
The max-tech efficiency levels correspond to units with the maximum
efficiency observed in each equipment class. Intermediate and max-tech
SCOP levels were translated into NSenCOP levels for the analyzed
equipment classes in order to perform the energy savings determination
analysis using the crosswalk analysis described in section II.A.1 of
this document. Table III.2 shows the efficiency levels in NSenCOP used
for the energy savings determination. Note that the table displays
results in terms of current net sensible cooling capacity ranges
(measured per the current DOE test procedure), rather than crosswalked
NSCC ranges (see section II.A of this NODA for further discussion of
the capacity crosswalk and equipment class switching issue for CRACs).
---------------------------------------------------------------------------
\25\ https://www.regulations.doe.gov/certification-data/CCMS-4-Air_Conditioners_and_Heat_Pumps_-_Computer_Room_Air_Conditioners.html#q=Product_Group_s%3A%22Air%20Conditioners%20and%20Heat%20Pumps%20-%20Computer%20Room%20Air%20Conditioners%22.
Table III.2--NSenCOP Efficiency Levels for CRACs Energy Savings Analysis
--------------------------------------------------------------------------------------------------------------------------------------------------------
Current
Equipment type Cooling medium Net sensible federal EL 0 * EL 1 EL 2 EL 3 EL 4 Max-Tech
cooling capacity standard
--------------------------------------------------------------------------------------------------------------------------------------------------------
(NSenCOP)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Upflow, non-ducted............... Glycol-Cooled >=65,000 Btu/h and 1.77 1.85 1.87 ** 1.89 1.99 2.14 ** 2.29
without a Fluid <240,000 Btu/h.
Economizer.
>=240,000 Btu/h and 1.73 1.75 1.78 ** 1.81 1.94 2.01 2.04
<760,000 Btu/h.
Glycol-Cooled with <65,000 Btu/h...... 1.99 2.00 2.04 ** 2.07 2.14 2.20 2.24
a Fluid Economizer.
>=65,000 Btu/h and 1.73 1.75 1.77 1.88 1.94 2.08 ** 2.22
<240,000 Btu/h.
>=240,000 Btu/h and 1.69 1.70 1.72 1.77 1.87 1.90 1.97
<760,000 Btu/h.
--------------------------------------------------------------------------------------------------------------------------------------------------------
* EL 0 represents the ASHRAE Standard 90.1-2016 level.
** EL was interpolated between adjacent levels.
c. Analysis Method and Annual Energy Use Results
To derive UECs for the equipment classes analyzed in this document,
DOE started with the adopted standard level UECs (i.e., the current DOE
standard) for the two glycol-cooled greater than 65,000 btu/h and three
glycol-cooled with a fluid economizer downflow equipment classes
analyzed in the May 2012 final rule. DOE assumed that these UECs
correspond to the NSenCOP
[[Page 48025]]
derived through the crosswalk analysis (i.e., ``Cross-walked Current
Federal Standard'' column in Table II.4). For higher efficiency levels,
DOE determined the UEC by dividing the baseline NSenCOP level by the
NSenCOP for each higher EL and multiplied the resulting percentage by
the baseline UEC.
In the May 2012 final rule, DOE assumed energy savings estimates
derived for downflow equipment classes would be representative of
upflow equipment classes which differed by a fixed 0.11 SCOP. 77 FR
28928, 28954 (May 16, 2012). Because of the fixed 0.11 SCOP difference
between upflow and downflow CRAC units in ASHRAE 90.1-2013, DOE
determined that the per-unit energy savings benefits for corresponding
CRACs at higher efficiency levels could be represented using the 15
downflow equipment classes. However, in this document, the efficiency
levels for the upflow non-ducted equipment classes do not differ from
the downflow equipment class by a fixed amount. For this document, DOE
assumed that the fractional increase/decrease in NSenCOP between upflow
and downflow units corresponds to a proportional decrease/increase in
the baseline UEC within a given equipment class grouping of condenser
system and capacity. Details can be found in chapter 3 of the CRAC/DOAS
NODA and RFI TSD.
CRAC Issue 3: DOE seeks comment on the appropriateness of using
UECs derived for the May 2012 final rule, specifically whether
energy use has changed significantly since the 2012 analysis due to
changes in operational behavior. DOE also requests feedback on
scaling UECs using NSenCOP values for higher efficiency levels.
CRAC Issue 4: DOE seeks comment on its approach to determining
the UEC of upflow units using the fractional increase or decrease in
NSenCOP relative to the baseline downflow unit in a given equipment
class grouping of condenser system and capacity.
Table III.3 and Table III.4 show UEC estimates for the equipment
classes amended by ASHRAE Standard 90.1-2016 (i.e., equipment classes
for which the ASHRAE Standard 90.1-2016 energy efficiency level is more
stringent than the current applicable Federal standard). The ``max-
tech'' levels represent the market maximum identified in DOE's
Compliance Certification Database and the California Energy Commission
(CEC) database as of March 2019.
Table III.3--National UEC Estimates (kWh/year) for Glycol-cooled,
Upflow, Non-Ducted CRACs
------------------------------------------------------------------------
>=65,000 Btu/h >=240,000 Btu/h
and <240,000 and <760,000
Btu/h Btu/h
------------------------------------------------------------------------
Baseline--Federal Standard............ 119,105 266,479
Efficiency Level 0.................... 113,955 263,434
Efficiency Level 1.................... 112,736 258,994
Efficiency Level 2.................... 111,543 254,701
Efficiency Level 3.................... 105,938 237,633
Efficiency Level 4.................... 98,512 229,358
Efficiency Level 5--``Max-Tech''...... 92,060 225,985
------------------------------------------------------------------------
Table III.4--National UEC Estimates (kWh/year) for Glycol-cooled With Fluid Economizer, Upflow, Non-Ducted CRACs
----------------------------------------------------------------------------------------------------------------
>=65,000 Btu/h >=240,000 Btu/
<65,000 Btu/h and <240,000 h and <760,000
Btu/h Btu/h
----------------------------------------------------------------------------------------------------------------
Baseline--Federal Standard...................................... 22,992 95,830 214,348
Efficiency Level 0.............................................. 22,877 94,735 213,087
Efficiency Level 1.............................................. 22,428 93,510 210,609
Efficiency Level 2.............................................. 22,103 88,135 204,741
Efficiency Level 3.............................................. 21,380 85,467 194,103
Efficiency Level 4.............................................. 20,797 79,690 191,082
Efficiency Level 5--``Max-Tech''................................ 20,426 74,678 183,986
----------------------------------------------------------------------------------------------------------------
2. Dedicated Outdoor Air Systems
a. Equipment Classes and Analytical Scope
DOE conducted an analysis of energy savings potential for two
equipment classes of DOASes: (1) DOAS, air-cooled, without energy
recovery and (2) DOAS, air-cooled, with energy recovery.
b. Efficiency Levels
DOE defines baseline efficiency levels, for each equipment class,
to serve as a basis of comparison for any changes in equipment cost and
energy use resulting from efficiency improvements that would be
required under potential amended standards. As discussed in section I.A
of this document, EPCA directs DOE to establish an amended ``uniform
national standard'' at the minimum level specified in the amended
ASHRAE Standard 90.1, unless it is determined by rule, and supported by
clear and convincing evidence, that adoption of a uniform national
standard more stringent that the amended ASHRAE Standard 90.1 would
result in significant additional conservation of energy and is
technologically feasible and economically justified. (42 U.S.C.
6313(a)(6)(A)(ii)) For the DOAS equipment classes evaluated in this
document, DOE selected baseline efficiency levels equivalent to the
performance standards established in ASHRAE Standard 90.1-2016; these
standards are specified in terms of ISMRE for dehumidification and
ISCOP for heating. Table III.5 shows the evaluated baseline efficiency
levels for air-cooled DOASes.
[[Page 48026]]
Table III.5--Baseline Efficiency Levels for Air-Cooled DOASes
------------------------------------------------------------------------
Baseline
Equipment class efficiency level
------------------------------------------------------------------------
Air-Cooled...................... w/o Energy 4.0 ISMRE
Recovery. 5.2 ISMRE
w/Energy Recovery.
------------------------------------------------------------------------
For each air-cooled DOAS equipment class, DOE analyzed several
efficiency levels. The AHRI Directory does not currently list DOAS
equipment performance ratings. Similarly, DOE was not able to find
ISMRE or ISCOP ratings in much of the manufacturer equipment
specifications. DOE notes that one manufacturer \26\ does provide
capacities, ISMRE, and ISCOP by equipment class. However, as discussed
in section II.B of this document, AHRI is currently revising AHRI 920,
and DOE notes that AHRI 920-Draft includes changes and clarifications
to the current industry test standard. Because of the current
development of updates to AHRI 920-2015, DOE decided not to rely on
existing ratings based on this test standard as the basis for the
efficiency levels established for this document.
---------------------------------------------------------------------------
\26\ Desert Aire DOAS Performance Catalog (Available at: http://www.desert-aire.com/sites/default/files/Brochure-DOAS-Performance-Catalog-DA430.pdf.pdf).
---------------------------------------------------------------------------
Instead, DOE relied on manufacturer equipment literature for
currently available 20-ton capacity air-cooled DOAS models with
sufficient design details of key components and performance data to
evaluate efficiency. DOE considered equipment that included EER and
IEER ratings based on the CUAC test procedure in appendix A, but that
were also capable of dehumidifying 100 percent outdoor air to a 55
[ordm]F dew point operating under Standard Rating Condition A, as
defined in ANSI/AHRI 920-2015. These included only air-cooled equipment
without energy recovery. DOE estimated the ISMRE for this equipment by
correlating EER to ISMRE based on manufacturer-provided data. As part
of this investigation, DOE also considered the specific incremental
design options used to achieve higher efficiency levels.
Based on this analysis, DOE is analyzing the two efficiency levels
above the baseline for air-cooled DOASes without energy recovery.
Although DOE did not identify any models with scaled EER-to-ISMRE
efficiencies using the correlation described above at the baseline
efficiency level, DOE determined based on manufacturer feedback that
the baseline design would likely include staged compressors, and that
the design change from the baseline efficiency level to EL 1 would
involve changing from staged compressor operation to variable-capacity
digital scroll compressors. The design changes from EL 1 to EL 2
include increasing the condenser heat exchanger size and fin density,
increasing the total condenser fans horsepower, and reducing the
capacity of the compressors needed.
For air-cooled DOASes with energy recovery, due to the similarity
in designs, DOE considered that the same design options and resulting
increase in efficiency from the analysis for DOASes without energy
recovery would be applied for the DOASes with energy recovery equipment
class.
Table III.6 presents the analyzed efficiency levels for both air-
cooled DOAS equipment classes.
Table III.6--Analyzed Incremental Efficiency Levels for Air-Cooled DOASes
----------------------------------------------------------------------------------------------------------------
Efficiency levels (ISMRE)
Equipment class -----------------------------------------------
Baseline EL 1 EL 2
----------------------------------------------------------------------------------------------------------------
Air-Cooled:
w/o Energy Recovery......................................... 4.0 5.0 6.0
w/Energy Recovery........................................... 5.2 6.2 7.2
----------------------------------------------------------------------------------------------------------------
DOAS Issue 3: DOE requests information about the ranges of ISMRE
and ISCOP levels that are available on the market by equipment class
and capacity, in order to assist with selection of efficiency
levels, including the market baseline.
c. Energy Use Simulations and Annual Energy Use Results
DOE used CBECS 2012 to develop a building sample to estimate the
baseline UEC for the two DOAS equipment classes. CBECS 2012 has two
variables that identify if a building's heating or cooling ventilation
is provided by a DOAS. CBECS 2012 also provides variables to indicate
the square footage per building, the representative national sample
weight for each building, the ventilation energy use, the cooling
energy use, and the main cooling equipment in a building. As CBECS 2012
uses separate variables for heating and cooling ventilation, DOE only
included buildings that used a DOAS for both heating and cooling
ventilation in its sample. The two DOAS equipment classes being
analyzed are both air cooled. Therefore, DOE built its sample using
buildings whose main cooling was provided by air-cooled equipment
(residential style AC, package air conditioners, and room air
conditioners).
The manufacturer literature shows that DOAS equipment is sized in
tons of cooling capacity; therefore, DOE began its analysis by
estimating the tons of cooling required for each building in the DOAS
sample. DOE used square footage per ton of cooling estimates, presented
in Table III.7 from PDH Online \27\ to calculate the tons of cooling
required for each building in the sample.
---------------------------------------------------------------------------
\27\ Bhatia, A., HVAC Refresher--Facilities Standard for the
Building Services (Part 2), PDH Online (Available at: https://pdhonline.com/courses/m216/m216content.pdf) (Last accessed March 28,
2019).
Table III.7--Square Footage per Ton of Cooling by Building Type
------------------------------------------------------------------------
Sq. ft. per
Building type ton of cooling
------------------------------------------------------------------------
Education............................................... 250
Enclosed mall........................................... 300
Food sales.............................................. 350
Food service............................................ 200
Healthcare.............................................. 280
Lodging................................................. 400
Non-refrigerated warehouse.............................. 400
Nursing................................................. 280
[[Page 48027]]
Office.................................................. 340
Public assembly......................................... * N/A
Religious............................................... * N/A
Retail (other than mall)................................ 300
Service................................................. 340
Strip shopping.......................................... 225
------------------------------------------------------------------------
* Sized based on occupancy, 20 people per ton
A DOAS is used for latent cooling and ventilation, and CBECS 2012
provides the cooling energy and ventilation energy for each building.
DOE divided the total ventilation energy use and the total cooling
energy use by the tons of cooling required for each building to come up
with a kWh/ton energy use metric per building. DOE then incorporated
the building weights to calculate a national weighted average kWh/ton
value for cooling and ventilation energy use. To determine the kWh/ton
for a DOAS, DOE added 30 percent \28\ of the cooling kWh/ton to the
ventilation kWh/ton. This accounts for latent cooling and ventilation
provided by the DOAS. DOE then multiplied the national weighted average
kWh/ton by 20 tons (the size of the representative capacity unit) to
determine the baseline energy use. CBECS 2012 does not provide
information about the existence of an energy recovery wheel; however,
manufacturer feedback has indicated that approximately 60 percent of
the DOASes sold do not have energy recovery wheels. Therefore, the kWh/
ton value from CBECS 2012 was used to determine the baseline unit
energy consumption (UEC) for DOASes without energy recovery. To
estimate the baseline UEC for DOASes with energy recovery, DOE scaled
the UECs based on the percentage difference between the ISMRE baseline
equipment without energy recovery and baseline equipment with energy
recovery. DOE calculated energy use for efficiency levels beyond the
ASHRAE baseline by dividing the baseline ISMRE by the ISMRE of each
higher efficiency level, for each equipment class. The resulting
percentage was then multiplied by the baseline UEC.
---------------------------------------------------------------------------
\28\ Sensible heat ratios in most buildings range between 0.6
and 0.8. Therefore, the latent portion of cooling load ranges from
0.2 to 0.4. DOE chose the midpoint for this exercise. (Available at:
https://www.engineeringtoolbox.com/shr-sensible-heat-ratio-d_700.html) (Last accessed April 3, 2019).
DOAS Issue 4: DOE requests comment on the appropriateness of
using the above approach to develop UECs for DOASes, whether
alternative assumptions should be made in the calculations, or
whether an alternate source of DOAS unit energy consumption values
is available. If DOE receives performance data for DOASes, then it
---------------------------------------------------------------------------
will derive UECs by matching building loads to DOAS performance.
Table III.8 show the UEC estimates for the ASHRAE Standard 90.1-
2016 levels, and the higher efficiency levels for the two air-cooled
DOAS equipment classes analyzed.
Table III.8--Annual Unit Energy Consumption for Air-Cooled DOASes by
Equipment Class
------------------------------------------------------------------------
Without heat With heat
Efficiency level recovery recovery
------------------------------------------------------------------------
EL 0--ASHRAE............................ 28,796 22,151
EL 1.................................... 23,037 18,578
EL 2--``Max Tech''...................... 19,198 15,998
------------------------------------------------------------------------
DOAS Issue 5: DOE requests data from field studies and
laboratory testing which show system performance curves and how
capacity and efficiency vary with outdoor air temperature, heating/
cooling load, ventilation load, and any other factors that impact
capacity and efficiency.
B. Shipments
DOE uses shipment projections by equipment class to calculate the
national impacts of standards on energy consumption, as well as net
present value and future manufacturer cash flows. DOE shipments
projections typically are based on available historical data broken out
by equipment. Current sales estimates allow for a more accurate model
that captures recent trends in the market.
1. Computer Room Air Conditioners
In the May 2012 final rule, as a result of lack of CRAC shipment
data for the United States, DOE estimated CRAC shipments by scaling
historical data for the Australian CRAC market based on the relative
number of businesses between the two countries and extrapolating
shipments for future years. 77 FR 28928, 28960 (May 16, 2012). However,
DOE stated that it is unknown whether the United States market mirrors
the Australian market or whether model availability approximates
shipment distributions. Id. at 28982. Thus, it is not fully clear the
extent to which historical shipments data of the Australian CRAC market
are representative of the current US market. In addition, a 2016 report
by the Lawrence Berkeley National Laboratory (LBNL) on data center
energy consumption \29\ noted trends toward consolidation of smaller
data centers into large, hyper-scale data centers which usually rely on
air handling units (AHU) with chilled water coils served by chillers
\30\ rather than CRACs. An extrapolation of historical trends may not
be appropriate as the small server rooms served by CRACs are replaced
by large, hyper-scale data centers. Accordingly, for this document, DOE
instead estimates CRAC shipments by analyzing trends in the cooling
demand required from CRAC-cooled data centers. DOE's approach in this
document estimates total annual shipments for the entire CRAC market
and then uses market share data to estimate shipments for ASHRAE
Standard 90.1-2016 triggered equipment classes.
---------------------------------------------------------------------------
\29\ Shehabi, A., Smith, S.J., Horner, N., Azevedo, I., Brown,
R., Koomey, J., Masanet, E., Sartor, D., Herrlin, M. and Lintner,
W., United States data center energy usage report (2016) Lawrence
Berkeley National Laboratory, Berkeley, California. LBNL-1005775
(Available at: https://datacenters.lbl.gov/sites/all/files/DataCenterEnergyReport2016_0.pdf) (Last accessed June 6, 2019).
\30\ DOE does not regulate the efficiency of chillers.
---------------------------------------------------------------------------
DOE first estimated the installed base stock of CRACs using
information on data centers in the 2012 Commercial Business Energy
Consumption Survey (CBECS). CBECS identifies buildings that contain
data centers, the number of servers in the data center, and associated
square footage. Although CBECS does not specifically inquire about the
presence of CRACs, DOE assumed any building identified as having a data
center that did not have a central chiller or district chilled water
system would be serviced by a CRAC. DOE assumed that a building with a
central chiller or district chilled water system would use a computer
room air handler (CRAH) and not a CRAC for its
[[Page 48028]]
data center cooling, and, thus, such building was not included in the
analysis.
CBECS includes buildings that do not identify the presence of a
data center, but do contain a significant number of servers, which
would require some form of dedicated cooling. DOE assumed buildings
with 10 or more servers that did not identify as having a data center
and did not have a central chiller or district chilled water system
would be serviced by CRAC units.
CRAC Issue 5: DOE assumed that buildings that do not identify
the presence of a data center, but contain more than 10 servers
would require a CRAC in the absence of a central chiller or district
chilled water system. DOE requests comment on the appropriateness of
using 10 servers as a threshold for assigning a CRAC unit for
cooling.
In order to estimate the CRAC cooling capacity required for each
data center in CBECS 2012, DOE first had to estimate the amount of heat
generated from servers, networks, and storage equipment within data
centers. Based on estimates from the LBNL data center report, DOE
estimated average power consumption of volume servers, network
equipment, and storage equipment at 330 Watts, 13 Watts, and 75 Watts,
respectively.\31\ Servers that were not in a data center were assumed
to only have network equipment, while servers in a data center had both
network and storage equipment, and thus a higher power draw.\32\ DOE
assumed 100 percent of the power draw was converted into heat exhaust
that would need to be removed by a CRAC. DOE calculated the cooling
load for each data center by multiplying the total server power draw by
the number of servers in each building with a data center or more than
10 servers in CBECS 2012. The total cooling load was then multiplied by
an oversize factor of 1.3. Oversizing of the cooling load gives the
data center operator the flexibility to add more servers (and thus more
heat) without having to increase the size of the cooling system.\33\
---------------------------------------------------------------------------
\31\ Shehabi, A., Smith, S.J., Horner, N., Azevedo, I., Brown,
R., Koomey, J., Masanet, E., Sartor, D., Herrlin, M. and Lintner,
W., United States data center energy usage report (2016), Lawrence
Berkeley National Laboratory, LBNL-1005775 (Available at: https://datacenters.lbl.gov/sites/all/files/DataCenterEnergyReport2016_0.pdf) (Last accessed June 6, 2019).
\32\ Id.
\33\ Rasmussen, N., Calculating Total Cooling Requirements for
Data Centers--White paper 25. Schneider Electric (Available at:
https://www.apcdistributors.com/white-papers/Cooling/WP-25%20Calculating%20Total%20Cooling%20Requirements%20for%20Data%20Centers.pdf) (Last accessed June 6, 2019).
CRAC Issue 6: DOE requests input and data on the typical amount
of oversizing employed by CRAC customers. DOE specifically requests
comment on its decision to use an oversize factor of 30 percent in
its energy use analysis. Additionally, DOE requests comment and
supporting data indicating whether the oversize factor would change
with equipment capacity or equipment class. DOE also requests
comment on whether it is appropriate to apply its cooling
calculation to data centers of all sizes.
CRAC Issue 7: DOE requests comment on its server power
consumption estimates and any information or data on expectations of
future server stock and energy use in small data centers.
One ton of cooling can remove 3.5 kW of heat from a space.\34\ All
data centers without central chillers were assumed to have CRACs, and
the cooling capacity of the CRAC units were based on the three
representative capacities analyzed in the May 2012 final rule. 77 FR
28928, 28954 (May 16, 2012). For CRACs with a cooling capacity of less
than 65,000 Btu/h, a 3-ton unit was assigned as the representative
capacity; cooling capacities from 65,000 Btu/h to 240,000 Btu/h were
assigned a representative capacity of 11 tons, and air conditioners
greater than or equal to 240,000 Btu/h and less than 760,000 Btu/h were
assigned a 24-ton unit.
---------------------------------------------------------------------------
\34\ Id.
---------------------------------------------------------------------------
The final part of the stock methodology is estimating the
redundancy requirements of the data center which reduces the per-unit
energy use and increases the total estimated shipment of CRACs.
Redundancy varies significantly across data centers ranging from having
one extra unit (N+1 redundancy) to having complete redundancy (2N
redundancy).\35\ DOE assigned redundancy depending on the data center
square footage provided in CBECS 2012. Categories 1-4 (data centers
under 10,000 square feet) were given N+1 redundancy; category 5
(greater than 10,000+ sq. ft.) was assigned 2N redundancy. DOE assumed
that servers that were not in a data center do not have cooling
redundancy.
---------------------------------------------------------------------------
\35\ Shehabi, A., Smith, S.J., Horner, N., Azevedo, I., Brown,
R., Koomey, J., Masanet, E., Sartor, D., Herrlin, M. and Lintner,
W., United States data center energy usage report (2016) Lawrence
Berkeley National Laboratory, LBNL-1005775 (Available at: https://datacenters.lbl.gov/sites/all/files/DataCenterEnergyReport2016_0.pdf) (Last accessed June 6, 2019).
CRAC Issue 8: DOE seeks information and comment on the ratio of
redundant to active equipment. DOE requests comment on whether
installed redundancy practices differ by customer type (i.e.,
private business versus government) or by CRAC capacity. If so, DOE
seeks information and comment on factors that would affect the ratio
---------------------------------------------------------------------------
of equipment redundancy for different consumers.
No-new standards case shipments (i.e., shipments in the absence of
an amended standard) were projected using the 2012 stock number of
CRACs estimated from CBECS 2012. From 2012, a linear trend was used to
develop a historical stock going back the average CRAC lifetime, which
is estimated to be 15 years (see section III.D.1 of this document). To
estimate the future market for CRACs given projected trends in data
centers, DOE then took the sample of buildings from CBECS 2012 used to
develop the 2012 stock and estimated what the stock would be in 2050.
DOE used two variables to change the stock: (1) A 10-percent reduction
in the number of servers in small data centers in 2050 and (2) a
doubling of the power per server in 2050. DOE then went about
calculating the stock using the same approach as described above. Once
the stock in 2050 was calculated, DOE used a linear approach to
estimate the stock for the years 2013-2049. New shipments were equal to
the year-over-year difference in stock, and replacements were equal to
the shipments from 15 years prior. Details can be found in chapter 4 of
the CRAC/DOAS NODA and RFI TSD.
As the power and density of individual servers increase, the
cooling load will increase, despite the reduction of the population of
servers in smaller data centers. While overall shipments are not
expected to change significantly between 2012 and 2050, there will be a
shift to CRACs with a larger cooling capacity. Table III.9 shows the
reference case shipments used to estimate potential energy savings.
[[Page 48029]]
Table III.9--Estimated CRAC Shipments by SCOP Net Sensible Cooling Capacity
----------------------------------------------------------------------------------------------------------------
>=65,000 Btu/h >=240,000 Btu/
<65,000 Btu/h and <240,000 h and <760,000 Total
Btu/h Btu/h shipments
----------------------------------------------------------------------------------------------------------------
2012 Shipments.................................. 8,522 779 671 9,973
2050 Shipments.................................. 6,198 2,884 1,197 10,279
----------------------------------------------------------------------------------------------------------------
DOE's analysis of CBECS server stock provides estimates of
shipments by cooling capacity. To further disaggregate shipments by
equipment class, DOE used model counts of units in DOE's Compliance
Certification Database. Table III.10 shows CRAC market share by
equipment class grouping. Note that the table displays results in terms
of current net sensible cooling capacity ranges (measured per the
current DOE test procedure), rather than crosswalked NSCC ranges (see
section II.A of this NODA for further discussion of the capacity
crosswalk and equipment class switching issue for CRACs).
Table III.10--Estimated Market Share for CRAC Equipment Classes by Equipment Class
----------------------------------------------------------------------------------------------------------------
>=65,000 Btu/h >=240,000 Btu/
Condenser system Orientation <65,000 Btu/h and <240,000 h and <760,000
* (%) Btu/h * (%) Btu/h * (%)
----------------------------------------------------------------------------------------------------------------
Air-cooled............................ Downflow................ 3.2 8.1 6.8
Upflow.................. 4.8 11.0 6.2
Water-cooled.......................... Downflow................ 1.2 4.0 1.2
Upflow.................. 2.2 4.6 1.6
Water-cooled with fluid economizer.... Downflow................ 1.8 5.5 1.2
Upflow.................. 1.7 6.1 2.1
Glycol-cooled......................... Downflow................ 1.1 2.7 0.5
Upflow.................. 2.1 3.3 0.5
Glycol-cooled with fluid economizer... Downflow................ 2.5 4.5 0.6
Upflow.................. 2.5 5.3 0.8
----------------------------------------------------------------------------------------------------------------
* Capacity measured per the current Federal test procedure.
DOE's Compliance Certification Database does not distinguish
between upflow ducted and upflow non-ducted CRACs. DOE assumed upflow
market share would be evenly split between the upflow ducted and upflow
non-ducted equipment classes. DOE's database also does not include
horizontal flow classes, as those models do not yet have standards.
Table III.11 presents CRAC shipments in 2018 and 2050 for equipment
classes analyzed for potential energy savings in this document. Note
that the capacity ranges for upflow, non-ducted equipment classes
listed in Table III.11 are not impacted by the change from SCOP to
NSenCOP (see section II.A.1 for details.)
Table III.11--Estimated Shipments for Equipment Classes Analyzed in This
Document
------------------------------------------------------------------------
Shipments in Shipments in
Equipment class 2018 2050
------------------------------------------------------------------------
Glycol-cooled, >=65,000 and <240,000 Btu/ 44 87
h, Upflow Non-ducted...................
Glycol-cooled, >=240,000 and <760,000 10 14
Btu/h, Upflow Non-ducted...............
Glycol-cooled with economizer, <65,000 412 329
Btu/h, Upflow Non-ducted...............
Glycol-cooled with economizer, >=65,000 72 139
and <240,000 Btu/h, Upflow Non-ducted..
Glycol-cooled with economizer, >=240,000 17 23
and <760,000 Btu/h, Upflow Non-ducted..
------------------------------------------------------------------------
CRAC Issue 9: DOE's approach to estimating energy savings relies
on estimates for annual shipments for the total CRAC market. DOE
seeks historical shipments data for CRACs and projections for growth
of the market based on trends stakeholders have observed.
Specifically, DOE requests as many years of historical shipments as
can be provided, consistent with the example table in Table III.12.
Table III.12--Request for Historical Shipments
----------------------------------------------------------------------------------------------------------------
2012 2013 2014 2015 2016 2017 2018
----------------------------------------------------------------------------------------------------------------
Annual CRAC Shipments.............. ......... ......... ......... ......... ......... ......... .........
----------------------------------------------------------------------------------------------------------------
CRAC Issue 10: In order to accurately disaggregate energy
savings by equipment class, DOE is interested in market data by
equipment class, efficiency level, and climatic region.
[[Page 48030]]
CRAC Issue 11: DOE requests data and feedback on its methodology
for determining market share by equipment class. DOE also requests
data on the breakdown of upflow units between upflow ducted and
upflow non-ducted and data on shipments for horizontal-flow
equipment classes.
CRAC Issue 12: DOE requests data and feedback on its stock
calculation, particularly data about the number of small data
centers that use CRACs, the assumption that buildings with a chiller
or chilled water system will not use CRACs, and any data or
information about the current stock of CRACs.
2. Dedicated Outdoor Air Systems
DOE developed its DOAS shipments estimates based on manufacturer
feedback that shipments in 2016 were around 36,000 units and that DOAS
growth is expected to be similar to that of VRF multi-split system
equipment. A report by Cadeo Group \36\ estimated VRF shipments to have
double-digit growth through 2022. Therefore, to project shipments past
2016, DOE used a 10-percent growth rate through 2022 and then followed
the same growth rate as other CUAC equipment, basing that growth rate
on the reference case shipment projections in the National Impact
Analysis spreadsheet \37\ from the January 15, 2016 direct final rule
for commercial unitary air conditioners and heat pumps and commercial
warm air furnaces. 81 FR 2420 (``CUAC-CUHP CWAF DFR'').
---------------------------------------------------------------------------
\36\ Cadeo report, Docket ID EERE-2017-BT-TP-0018-0002.
\37\ DOE Energy Conservation Standards for Small, Large, and
Very Large Air-Cooled Commercial Package Air Conditioning and
Heating Equipment, National Impact Analysis spreadsheet (Available
at: https://www.regulations.gov/document?D=EERE-2013-BT-STD-0007-0107).
---------------------------------------------------------------------------
Manufacturers estimate that air-cooled DOASes represent 95 percent
of all DOAS shipments, and DOE assumed that this percentage would
remain constant for the duration of the 30-year shipments analysis. As
DOE is only analyzing the two air-cooled DOAS equipment classes, DOE
reduced the annual shipments projections developed above by 5 percent
to capture only the air-cooled product classes. Next, DOE allocated 59-
percent of shipments to air-cooled DOAS without energy recovery and 41-
percent of shipments to air-cooled DOAS with energy recovery, based on
manufacturer estimates of the breakdown by product class.
DOAS Issue 6: DOE seeks historical data on DOAS shipments and
forecasted growth of DOAS shipments by efficiency level, equipment
class, and capacity.
DOAS Issue 7: DOE seeks information about the most common kinds
of local, in-space cooling system with which a DOAS is paired. DOE
seeks comment on the assumption that DOAS shipments will grow in
line with VRF multi-split systems and water-source heat pumps in
future years.
C. No-New-Standards-Case Efficiency Distribution
For CRACs, DOE estimated the no-new-standards case efficiency
distributions for each equipment class using model counts from DOE's
Compliance Certification Database. DOE bundled the efficiency levels
into ``efficiency ranges'' and determined the percentage of models
within each range. The distribution of efficiencies in the no-new-
standards case for each equipment class can be found in chapter 4 of
the CRAC/DOAS NODA and RFI TSD. DOE did not have any information on the
market share of DOASes; therefore, a uniform distribution was used with
1/3rd of the market at each efficiency level to estimate national
energy savings.
For the standards cases for all equipment addressed in this
document, DOE assumed shipments at lower efficiencies were most likely
to roll up into higher efficiency levels in response to more-stringent
standards. For each efficiency level analyzed within a given equipment
class, DOE used a ``roll-up'' scenario to establish the market shares
by efficiency level for the year that standards would become effective
(e.g., 2019, 2020, or 2023). Available information also suggests that
all equipment efficiencies in the no-new standards case that were above
the standard level under consideration would not be affected. Table
III.13 shows the no-new standards case efficiency distribution for
CRACs.
Table III.13--CRACs No-New-Standards-Case Efficiency Distribution
----------------------------------------------------------------------------------------------------------------
Federal Level 0 Level 1 Level 2 Level 3 Level 4 Level 5 Total
Equipment class (%) (%) (%) (%) (%) (%) (%) (%)
----------------------------------------------------------------------------------------------------------------
Glycol-cooled, Upflow, Non- 35.6 6.8 3.4 18.6 30.5 3.4 1.7 100
ducted, >=65,000 Btu/h and
<240,000 Btu/h.................
Glycol-cooled, Upflow, Non- 22.2 22.2 0.0 11.1 11.1 11.1 22.2 100
ducted, >=240,000 Btu/h........
Glycol-cooled with a Fluid 0.0 0.0 4.5 4.5 31.8 45.5 13.6 100
Economizer, Upflow, Non-ducted,
<65,000 Btu/h..................
Glycol-cooled with a Fluid 12.6 10.5 29.5 22.1 23.2 1.1 1.1 100
Economizer, Upflow, Non-ducted,
>=65,000 Btu/h and <240,000 Btu/
h..............................
Glycol-cooled with a Fluid 0.0 26.7 33.3 6.7 6.7 13.3 13.3 100
Economizer, Upflow, Non-ducted,
>=240,000......................
----------------------------------------------------------------------------------------------------------------
CRAC Issue 13: DOE seeks input on its determination of the no-
new-standards case distribution of efficiencies for CRACs and its
projection of how amended energy conservation standards would affect
the distribution of efficiencies in each standards case.
DOAS Issue 8: DOE also seeks input on how best to determine the
no-standards-case efficiency distribution for DOASes.
Using the distribution of efficiencies in the no-new-standards case
and in the standards cases for each equipment class analyzed in this
document, as well as the UECs for each specified efficiency level
(discussed previously), DOE calculated market-weighted average
efficiency values. The market-weighted average efficiency value
represents the average efficiency of the total units shipped at a
specified amended standard level. The market-weighted average
efficiency values for the no-new-standards case and the standards cases
for each efficiency level analyzed within the equipment classes is
provided in chapter 4 of the CRAC/DOAS NODA and RFI TSD.
DOAS Issue 9: DOE seeks historical shipment-weighted efficiency
data for DOASes by equipment class.
D. Other Analytical Inputs
1. Equipment Lifetime
DOE defines ``equipment lifetime'' as the age at which a unit is
retired from service. DOE used a 15-year lifetime for all CRAC
equipment classes. This is the average lifetime used in the May 2012
final rule. 77 FR 28928, 28958 (May 16, 2012).
[[Page 48031]]
CRAC Issue 14: DOE requests any data or information regarding
whether 15 years is an appropriate average value for CRAC equipment
lifetime and whether equipment lifetime varies based on equipment
class and/or efficiency level.
DOE does not have any data on the lifetime of DOASes; however, DOE
did develop a lifetime model for commercial package air conditioners in
the January 2016 CUAC-CUHP-CWAF DFR.\38\ As DOASes are also package, DX
equipment, DOE used the lifetimes it developed for 15-ton commercial
package air conditioners to estimate the lifetime of DOASes. DOE
calculated a mean lifetime of 22.6 years from the annual failure rates
developed for 15-ton CUACs from the life-cycle model of the January
2016 CUAC-CUHP-CWAF DFR.\39\ DOE used this mean lifetime of 22.6 years
in its DOAS analysis.
---------------------------------------------------------------------------
\38\ Direct Final Rule Life-Cycle-Cost Analysis Spreadsheet
(Available at: https://www.regulations.gov/document?D=EERE-2013-BT-STD-0007-0106).
\39\ Direct Final Rule Life-Cycle-Cost Analysis Spreadsheet
(Available at: https://www.regulations.gov/document?D=EERE-2013-BT-STD-0007-0106).
DOAS Issue 10: DOE requests any data or information about the
lifetime of DOASes and whether the equipment lifetime varies based
on equipment class, condenser type, capacity, and efficiency level.
In the absence of data about the lifetime of DOASes, DOE requests
comment on the appropriateness of applying the lifetime developed
for the January 2016 CUAC-CUHP CWAF DFR.
2. Compliance Dates and Analysis Period
If DOE were to prescribe energy conservation standards at the
efficiency levels contained in ASHRAE Standard 90.1-2016, EPCA states
that any such standard shall become effective on or after a date that
is two or three years (depending on the equipment type or size) after
the effective date of the applicable minimum energy efficiency
requirement in the amended ASHRAE standard. (42 U.S.C. 6313(a)(6)(D))
If DOE were to prescribe standards more stringent than the efficiency
levels contained in ASHRAE Standard 90.1-2016, EPCA dictates that any
such standard will become effective for equipment manufactured on or
after a date which is four years after the date of publication of a
final rule in the Federal Register. (42 U.S.C. 6313(a)(6)(D)) For
equipment classes where DOE is acting under its 6-year-lookback
authority, if DOE were to adopt more-stringent standards, EPCA states
that any such standard shall apply to equipment manufactured after a
date that is the latter of the date three years after publication of
the final rule establishing such standard or six years after the
effective date for the current standard. (42 U.S.C. 6313(a)(6)(C)(iv))
For purposes of calculating the NES for the equipment in this
evaluation, DOE used a 30-year analysis period starting with the
assumed year of compliance listed in Table III.14 for each equipment
class. This is the standard analysis period of 30 years that DOE
typically uses in its NES analysis. For equipment classes with a
compliance date in the last six months of the year, DOE starts its
analysis period in the first full year after compliance. For example,
if CRACs greater than 65,000 Btu/h and less than 240,000 Btu/h were to
have a compliance date of October 26, 2019, the analysis period for
calculating NES would begin in 2020 and extend to 2049.
While the analysis periods remain the same for assessing the energy
savings of efficiency levels higher than the ASHRAE levels, those
energy savings would not begin accumulating until 2023 (the assumed
compliance date if DOE were to determine that standard levels more
stringent than the ASHRAE levels are justified).
Table III.14--Approximate Compliance Date of an Amended Energy
Conservation Standard for Each Equipment Class
------------------------------------------------------------------------
Approximate
Approximate compliance date
compliance date for adopting more-
for adopting the stringent
Equipment class efficiency levels efficiency levels
in ASHRAE than those in
standard 90.1- ASHRAE standard
2016 90.1-2016
------------------------------------------------------------------------
Computer Room Air Conditioners
------------------------------------------------------------------------
CRAC, Glycol-Cooled, >=65,000 and 10/26/2019 4/26/2023
<240,000 Btu/h, Upflow Non-ducted
CRAC, Glycol-Cooled, >=240,000 Btu/ 10/26/2019 4/26/2023
h and <760,000 Btu/h, Upflow Non-
ducted...........................
CRAC, Glycol-Cooled with fluid 10/26/2018 4/26/2023
economizer, <65,000 Btu/h, Upflow
Non-ducted.......................
CRAC, Glycol-Cooled with fluid 10/26/2019 4/26/2023
economizer, >=65,000 and <240,000
Btu/h, Upflow Non-ducted.........
CRAC, Glycol-Cooled with fluid 10/26/2019 4/26/2023
economizer, >=240,000 Btu/h and
<760,000 Btu/h, Upflow Non-Ducted
------------------------------------------------------------------------
Dedicated Outdoor Air Systems
------------------------------------------------------------------------
All Equipment Classes............. 10/26/2019 4/26/2023
------------------------------------------------------------------------
E. Other Energy Conservation Standards Topics
1. Market Failures
In the field of economics, a market failure is a situation in which
the market outcome does not maximize societal welfare. Such an outcome
would result in unrealized potential welfare. DOE welcomes comment on
any aspect of market failures, especially those in the context of
amended energy conservation standards for CRACs and DOASes.
2. Network Mode/``Smart'' Equipment
DOE recently published an RFI on the emerging smart technology
appliance and equipment market. 83 FR 46886 (Sept. 17, 2018). In that
RFI, DOE sought information to better understand market trends and
issues in the emerging market for appliances and commercial
[[Page 48032]]
equipment that incorporate smart technology. DOE's intent in issuing
the RFI was to ensure that DOE did not inadvertently impede such
innovation in fulfilling its statutory obligations in setting
efficiency standards for covered products and equipment. DOE seeks
comments, data, and information on the issues presented in the RFI as
they may be applicable to CRACs and DOASes.
3. Other
In addition to the issues identified earlier in this document, DOE
welcomes comment on any other aspect of energy conservation standards
for CRACs and DOASes not already addressed by the specific areas
identified in this document.
F. Estimates of Potential Energy Savings
DOE estimated the potential primary and full-fuel cycle (FFC)
energy savings in quads (i.e., 10\15\ Btu) for each efficiency level
considered within each equipment class analyzed. The potential energy
savings for efficiency levels more stringent than those specified by
ASHRAE Standard 90.1-2016 were calculated relative to the efficiency
levels that would result if ASHRAE Standard 90.1-2016 standards were
adopted. Table III.15 through Table III.17 show the potential energy
savings resulting from the analyses conducted. The reported energy
savings are cumulative over the period in which equipment shipped in
the 30-year analysis continues to operate.
Table III.15--Potential Energy Savings for CRACs, Glycol-Cooled, Upflow, Non-Ducted
----------------------------------------------------------------------------------------------------------------
>=65,000 Btu/h and <240,000 >=240,000 Btu/h and <760,000
Btu/h [dagger] Btu/h [dagger]
---------------------------------------------------------------
NSenCOP quads NSenCOP quads
----------------------------------------------------------------------------------------------------------------
Site Energy Savings Estimate (quads)
----------------------------------------------------------------------------------------------------------------
Level 0......................................... 1.85 0.000 1.75 0.000
Level 1......................................... 1.87 0.000 1.78 0.000
Level 2......................................... 1.89 0.000 1.81 0.000
Level 3......................................... 1.99 0.000 1.94 0.000
Level 4......................................... 2.14 0.001 2.01 0.000
Level 5--``Max Tech''........................... 2.29 0.002 2.04 0.000
----------------------------------------------------------------------------------------------------------------
Primary Energy Savings Estimate (quads)
----------------------------------------------------------------------------------------------------------------
Level 0......................................... 1.85 0.000 1.75 0.000
Level 1......................................... 1.87 0.000 1.78 0.000
Level 2......................................... 1.89 0.000 1.81 0.000
Level 3......................................... 1.99 0.001 1.94 0.001
Level 4......................................... 2.14 0.003 2.01 0.001
Level 5--``Max Tech''........................... 2.29 0.004 2.04 0.001
----------------------------------------------------------------------------------------------------------------
FFC Energy Savings Estimate (quads)
----------------------------------------------------------------------------------------------------------------
Level 0......................................... 1.85 0.000 1.75 0.000
Level 1......................................... 1.87 0.000 1.78 0.000
Level 2......................................... 1.89 0.000 1.81 0.000
Level 3......................................... 1.99 0.001 1.94 0.001
Level 4......................................... 2.14 0.003 2.01 0.001
Level 5--``Max Tech''........................... 2.29 0.005 2.04 0.001
----------------------------------------------------------------------------------------------------------------
[dagger] The potential energy savings for Level 0 (the ASHRAE Standard 90.1-2016 level) were calculated relative
to the Federal standard. The potential energy savings for efficiency Levels 1-5 were calculated relative to
Level 0.
Table III.16--Potential Energy Savings for CRACs, Glycol-Cooled With a Fluid Economizer, Upflow, Non-Ducted
--------------------------------------------------------------------------------------------------------------------------------------------------------
<65,000 Btu/h [dagger] >=65,000 Btu/h and <240,000 >=240,000 Btu/h and <760,000
-------------------------------- Btu/h [dagger] Btu/h [dagger]
---------------------------------------------------------------
NSenCOP quads NSenCOP quads NSenCOP quads
--------------------------------------------------------------------------------------------------------------------------------------------------------
Site Energy Savings Estimate (quads)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Level 0................................................. 2.00 0.000 1.75 0.000 1.70 0.000
Level 1................................................. 2.04 0.000 1.77 0.000 1.72 0.000
Level 2................................................. 2.07 0.000 1.88 0.000 1.77 0.000
Level 3................................................. 2.14 0.000 1.94 0.001 1.87 0.000
Level 4................................................. 2.20 0.000 2.08 0.002 1.90 0.000
Level 5--``Max Tech''................................... 2.24 0.000 2.22 0.002 1.97 0.001
--------------------------------------------------------------------------------------------------------------------------------------------------------
Primary Energy Savings Estimate (quads)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Level 0................................................. 2.00 0.000 1.75 0.000 1.70 0.000
Level 1................................................. 2.04 0.000 1.77 0.000 1.72 0.000
Level 2................................................. 2.07 0.000 1.88 0.001 1.77 0.000
Level 3................................................. 2.14 0.000 1.94 0.002 1.87 0.001
Level 4................................................. 2.20 0.000 2.08 0.004 1.90 0.001
[[Page 48033]]
Level 5--``Max Tech''................................... 2.24 0.001 2.22 0.006 1.97 0.001
--------------------------------------------------------------------------------------------------------------------------------------------------------
FFC Energy Savings Estimate (quads)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Level 0................................................. 2.00 0.000 1.75 0.000 1.70 0.000
Level 1................................................. 2.04 0.000 1.77 0.000 1.72 0.000
Level 2................................................. 2.07 0.000 1.88 0.001 1.77 0.000
Level 3................................................. 2.14 0.000 1.94 0.002 1.87 0.001
Level 4................................................. 2.20 0.000 2.08 0.004 1.90 0.001
Level 5--``Max Tech''................................... 2.24 0.001 2.22 0.006 1.97 0.001
--------------------------------------------------------------------------------------------------------------------------------------------------------
[dagger] The potential energy savings for Level 0 (the ASHRAE Standard 90.1-2016 level) were calculated relative to the Federal standard. The potential
energy savings for efficiency Levels 1-5 were calculated relative to Level 0.
Table III.17--Potential Energy Savings for Air-Cooled DOASes
----------------------------------------------------------------------------------------------------------------
Without energy recovery With energy recovery
Efficiency Level ---------------------------------------------------------------
ISMRE quads ISMRE quads
----------------------------------------------------------------------------------------------------------------
Site Energy Savings Estimate
----------------------------------------------------------------------------------------------------------------
Level 0--ASHRAE................................. 4.0 .............. 5.2 ..............
Level 1......................................... 5.0 0.155 6.2 0.067
Level 2 = ``Max Tech''.......................... 6.0 0.362 7.2 0.164
----------------------------------------------------------------------------------------------------------------
Primary Energy Savings Estimate
----------------------------------------------------------------------------------------------------------------
Level 0--ASHRAE................................. 4.0 .............. 5.2 ..............
Level 1......................................... 5.0 0.408 6.2 0.176
Level 2 = ``Max Tech''.......................... 6.0 0.951 7.2 0.431
----------------------------------------------------------------------------------------------------------------
FFC Energy Savings Estimate
----------------------------------------------------------------------------------------------------------------
Level 0--ASHRAE................................. 4.0 .............. 5.2 ..............
Level 1......................................... 5.0 0.426 6.2 0.184
Level 2 = ``Max Tech''.......................... 6.0 0.994 7.2 0.450
----------------------------------------------------------------------------------------------------------------
IV. Review Under Six-Year Lookback Provisions: Requested Information
As discussed, DOE is required to conduct an evaluation of each
class of covered equipment in ASHRAE Standard 90.1 every 6 years. (42
U.S.C. 6313(a)(6)(C)(i)) Accordingly, DOE is also evaluating the
remaining 40 CRAC equipment classes for which ASHRAE Standard 90.1-2016
did not increase the stringency of the standards. In making a
determination of whether standards for such equipment need to be
amended, DOE must also follow specific statutory criteria. Similar to
the consideration of whether to adopt a standard more stringent than an
amended ASHRAE Standard 90.1 level, DOE must evaluate whether amended
Federal standards would result in significant additional conservation
of energy and are technologically feasible and economically justified.
(42 U.S.C. 6313(a)(6)(C)(i)(I) (referencing 42 U.S.C.
6313(a)(6)(A)(ii)(II)) A determination of whether more-stringent
standards are economically justified in the context of the six-year
look-back provision requires an analysis under the same seven factors
EPCA established for determining whether standards more stringent than
an amended ASHRAE standard are required. (42 U.S.C.
6313(a)(6)(C)(i)(II) (referencing 42 U.S.C. 6313(a)(6)(B)(i)(I)-(VII))
(See section III)
As the analysis of more-stringent standards for those equipment
classes of CRACs for which ASHRAE 90.1-2016 did not increase stringency
of efficiency levels is similar to the analysis for those equipment
classes for which ASHRAE 90.1-2016 did increase stringency of
efficiency levels, the issues identified in section III apply to both
sets of equipment classes. Specifically, for the 40 equipment classes
of CRACs for which ASHRAE Standard 90.1-2016 does not specify energy
efficiency levels more stringent than the currently applicable Federal
standards, DOE requests comment and information on the following
issues:
Annual Energy Use
CRAC Issue 15: DOE seeks comment on the appropriateness of using
UECs derived for the May 2012 final rule, specifically whether
energy use has changed significantly since the 2012 analysis due to
changes in operational behavior. DOE also requests feedback on
scaling UECs using NSenCOP values for higher efficiency levels.
CRAC Issue 16: DOE seeks comment on its approach to determining
the UEC of upflow units using the fractional increase or decrease in
NSenCOP relative to the baseline downflow unit in a given equipment
class grouping of condenser system and capacity.
Shipments
CRAC Issue 17: DOE assumed that buildings that do not identify
the presence of a data center, but contain more than 10 servers
would require a CRAC in the absence of a central chiller or district
chilled water system. DOE requests comment on the appropriateness of
using 10 servers as a threshold for assigning a CRAC unit for
cooling.
[[Page 48034]]
CRAC Issue 18: DOE requests input and data on the typical amount
of oversizing employed by CRAC customers. DOE specifically requests
comment on its decision to use an oversize factor of 30 percent in
its energy use analysis. Additionally, DOE requests comment and
supporting data indicating whether the oversize factor would change
with equipment capacity or equipment class. DOE also requests
comment on whether it is appropriate to apply its cooling
calculation to data centers of all sizes.
CRAC Issue 19: DOE requests comment on its server power
consumption estimates and any information or data on expectations of
future server stock and energy use in small data centers.
CRAC Issue 20: DOE's approach to estimating energy savings
relies on estimates for annual shipments for the total CRAC market.
DOE seeks historical shipments data for CRACs and projections for
growth of the market based on trends stakeholders have observed.
Specifically, DOE requests as many years of historical shipments as
can be provided with an example table requested in Table IV.1.
Table IV.1--Request for Historical Shipments
----------------------------------------------------------------------------------------------------------------
2012 2013 2014 2015 2016 2017 2018
----------------------------------------------------------------------------------------------------------------
Annual CRAC Shipments.............. ......... ......... ......... ......... ......... ......... .........
----------------------------------------------------------------------------------------------------------------
CRAC Issue 21: In order to accurately disaggregate energy
savings by equipment class, DOE is interested in market data by
equipment class, efficiency level, and climatic region.
CRAC Issue 22: DOE requests data and feedback on its methodology
for determining market share by equipment class.
CRAC Issue 23: DOE requests data and feedback on its stock
calculation, particularly data about the number of small data
centers that use CRACs, the assumption that buildings with chiller
or chilled water system will not use CRACs, and any data or
information about the current stock of CRACs.
No-New-Standards-Case Efficiency Distribution
CRAC Issue 24: DOE seeks input on its determination of the no-
new-standards case distribution of efficiencies for CRACs and its
projection of how amended standards would affect the distribution of
efficiencies in each standards case.
Equipment Lifetime
CRAC Issue 25: DOE requests any data or information regarding
whether 15 years is an appropriate average value for CRAC equipment
lifetime and whether equipment lifetime varies based on equipment
class and/or efficiency level.
V. Public Participation
A. Submission of Comments
DOE invites all interested parties to submit in writing by the date
specified previously in the DATES section of this document, comments,
data, and information on matters addressed in this document and on
other matters relevant to DOE's consideration of amended energy
conservation standards for CRACs and DOASes. Interested parties may
submit comments, data, and other information using any of the methods
described in the ADDRESSES section at the beginning of this document.
Submitting comments via http://www.regulations.gov. The http://www.regulations.gov. Web page will require you to provide your name and
contact information. Your contact information will be viewable to DOE
Building Technologies staff only. Your contact information will not be
publicly viewable except for your first and last names, organization
name (if any), and submitter representative name (if any). If your
comment is not processed properly because of technical difficulties,
DOE will use this information to contact you. If DOE cannot read your
comment due to technical difficulties and cannot contact you for
clarification, DOE may not be able to consider your comment.
However, your contact information will be publicly viewable if you
include it in the comment itself or in any documents attached to your
comment. Any information that you do not want to be publicly viewable
should not be included in your comment, nor in any document attached to
your comment. Otherwise, persons viewing comments will see only first
and last names, organization names, correspondence containing comments,
and any documents submitted with the comments.
Do not submit to http://www.regulations.gov information for which
disclosure is restricted by statute, such as trade secrets and
commercial or financial information (hereinafter referred to as
Confidential Business Information (CBI)). Comments submitted through
http://www.regulations.gov cannot be claimed as CBI. Comments received
through the website will waive any CBI claims for the information
submitted. For information on submitting CBI, see the Confidential
Business Information section.
DOE processes submissions made through http://www.regulations.gov
before posting. Normally, comments will be posted within a few days of
being submitted. However, if large volumes of comments are being
processed simultaneously, your comment may not be viewable for up to
several weeks. Please keep the comment tracking number that http://www.regulations.gov provides after you have successfully uploaded your
comment.
Submitting comments via email, hand delivery/courier, or postal
mail. Comments and documents submitted via email, hand delivery/
courier, or postal mail also will be posted to http://www.regulations.gov. If you do not want your personal contact
information to be publicly viewable, do not include it in your comment
or any accompanying documents. Instead, provide your contact
information in a cover letter. Include your first and last names, email
address, telephone number, and optional mailing address. The cover
letter will not be publicly viewable as long as it does not include any
comments.
Include contact information each time you submit comments, data,
documents, and other information to DOE. If you submit via postal mail
or hand delivery/courier, please provide all items on a CD, if
feasible, in which case it is not necessary to submit printed copies.
Comments, data, and other information submitted to DOE
electronically should be provided in PDF (preferred), Microsoft Word or
Excel, WordPerfect, or text (ASCII) file format. Provide documents that
are not secured, that are written in English, and that are free of any
defects or viruses. Documents should not contain special characters or
any form of encryption.
Campaign form letters. Please submit campaign form letters by the
originating organization in batches of between 50 to 500 form letters
per PDF or as one form letter with a list of supporters' names compiled
into one or more PDFs. This reduces comment processing and posting
time.
Confidential Business Information. Pursuant to 10 CFR 1004.11, any
person submitting information that he or she believes to be
confidential and exempt by law from public disclosure should submit via
email, postal mail, or hand delivery/courier two well-marked
[[Page 48035]]
copies: one copy of the document marked ``confidential'' including all
the information believed to be confidential, and one copy of the
document marked ``non-confidential'' with the information believed to
be confidential deleted. Submit these documents via email or on a CD,
if feasible. DOE will make its own determination about the confidential
status of the information and treat it according to its determination.
Factors of interest to DOE when evaluating requests to treat
submitted information as confidential include: (1) A description of the
items, (2) whether and why such items are customarily treated as
confidential within the industry, (3) whether the information is
generally known by or available from other sources, (4) whether the
information has previously been made available to others without
obligation concerning its confidentiality, (5) an explanation of the
competitive injury to the submitting person which would result from
public disclosure, (6) when such information might lose its
confidential character due to the passage of time, and (7) why
disclosure of the information would be contrary to the public interest.
It is DOE's policy that all comments may be included in the public
docket, without change and as received, including any personal
information provided in the comments (except information deemed to be
exempt from public disclosure).
DOE considers public participation to be a very important part of
the process for developing energy conservation standards. DOE actively
encourages the participation and interaction of the public during the
comment period in each stage of the rulemaking process. Interactions
with and between members of the public provide a balanced discussion of
the issues and assist DOE in the rulemaking process. Anyone who wishes
to be added to the DOE mailing list to receive future notices and
information about this process or would like to request a public
meeting should contact Appliance and Equipment Standards Program staff
at (202) 287-1445 or via email at
[email protected].
B. Issues on Which DOE Seeks Comment
DOE welcomes comments on any aspect of this document for CRAC and
DOAS equipment classes where ASHRAE Standard 90.1-2016 increased
stringency (thereby triggering DOE's review of amended standards) and
for CRAC and DOAS equipment classes undergoing 6-year-lookback review.
DOE is particularly interested in receiving comments and views of
interested parties concerning the following issues, listed by equipment
category:
CRAC Issue 1: DOE seeks comment on whether, in the context of
its consideration of more-stringent standards, there have been
sufficient technological or market changes for CRACs since the most
recent standards update that may justify a new rulemaking to
consider more-stringent standards. Specifically, DOE seeks data and
information that could enable the agency to determine whether DOE
should propose a ``no new standard'' determination because a more-
stringent standard: (1) Would not result in significant additional
savings of energy; (2) is not technologically feasible; (3) is not
economically justified; or (4) any combination of the foregoing.
CRAC Issue 2: DOE requests comment on the methodology and
results for the crosswalk analysis.
CRAC Issue 3: DOE seeks comment on the appropriateness of using
UECs derived for the May 2012 final rule, specifically whether
energy use has changed significantly since the 2012 analysis due to
changes in operational behavior. DOE also requests feedback on
scaling UECs using NSenCOP values for higher efficiency levels.
CRAC Issue 4: DOE seeks comment on its approach to determining
the UEC of upflow units using the fractional increase or decrease in
NSenCOP relative to the baseline downflow unit in a given equipment
class grouping of condenser system and capacity.
CRAC Issue 5: DOE assumed that buildings that do not identify
the presence of a data center, but contain more than 10 servers
would require a CRAC in the absence of a central chiller or district
chilled water system. DOE requests comment on the appropriateness of
using 10 servers as a threshold for assigning a CRAC unit for
cooling.
CRAC Issue 6: DOE requests input and data on the typical amount
of oversizing employed by CRAC customers. DOE specifically requests
comment on its decision to use an oversize factor of 30 percent in
its energy use analysis. Additionally, DOE requests comment and
supporting data indicating whether the oversize factor would change
with equipment capacity or equipment class. DOE also requests
comment on whether it is appropriate to apply its cooling
calculation to data centers of all sizes.
CRAC Issue 7: DOE requests comment on its server power
consumption estimates and any information or data on expectations of
future server stock and energy use in small data centers.
CRAC Issue 8: DOE seeks information and comment on the ratio of
redundant to active equipment. DOE requests comment on whether
installed redundancy practices differ by customer type (i.e.,
private business versus government) or by CRAC capacity. If so, DOE
seeks information and comment on factors that would affect the ratio
of equipment redundancy for different consumers.
CRAC Issue 9: DOE's approach to estimating energy savings relies
on estimates for annual shipments for the total CRAC market. DOE
seeks historical shipments data for CRACs and projections for growth
of the market based on trends stakeholders have observed.
Specifically, DOE requests as many years of historical shipments as
can be provided, consistent with the example table in Table III.12.
CRAC Issue 10: In order to accurately disaggregate energy
savings by equipment class, DOE is interested in market data by
equipment class, efficiency level, and climatic region.
CRAC Issue 11: DOE requests data and feedback on its methodology
for determining market share by equipment class. DOE also requests
data on the breakdown of upflow units between upflow ducted and
upflow non-ducted and data on shipments for horizontal-flow
equipment classes.
CRAC Issue 12: DOE requests data and feedback on its stock
calculation, particularly data about the number of small data
centers that use CRACs, the assumption that buildings with a chiller
or chilled water system will not use CRACs, and any data or
information about the current stock of CRACs.
CRAC Issue 13: DOE seeks input on its determination of the no-
new-standards case distribution of efficiencies for CRACs and its
projection of how amended energy conservation standards would affect
the distribution of efficiencies in each standards case.
CRAC Issue 14: DOE requests any data or information regarding
whether 15 years is an appropriate average value for CRAC equipment
lifetime and whether equipment lifetime varies based on equipment
class and/or efficiency level.
CRAC Issue 15: DOE seeks comment on the appropriateness of using
UECs derived for the May 2012 final rule, specifically whether
energy use has changed significantly since the 2012 analysis due to
changes in operational behavior. DOE also requests feedback on
scaling UECs using NSenCOP values for higher efficiency levels.
CRAC Issue 16: DOE seeks comment on its approach to determining
the UEC of upflow units using the fractional increase or decrease in
NSenCOP relative to the baseline downflow unit in a given equipment
class grouping of condenser system and capacity.
CRAC Issue 17: DOE assumed that buildings that do not identify
the presence of a data center, but contain more than 10 servers
would require a CRAC in the absence of a central chiller or district
chilled water system. DOE requests comment on the appropriateness of
using 10 servers as a threshold for assigning a CRAC unit for
cooling.
CRAC Issue 18: DOE requests input and data on the typical amount
of oversizing employed by CRAC customers. DOE specifically requests
comment on its decision to use an oversize factor of 30 percent in
its energy use analysis. Additionally, DOE requests comment and
supporting data indicating whether the oversize factor would change
with equipment capacity or equipment class. DOE also requests
comment on whether it is appropriate to apply its cooling
calculation to data centers of all sizes.
[[Page 48036]]
CRAC Issue 19: DOE requests comment on its server power
consumption estimates and any information or data on expectations of
future server stock and energy use in small data centers.
CRAC Issue 20: DOE's approach to estimating energy savings
relies on estimates for annual shipments for the total CRAC market.
DOE seeks historical shipments data for CRACs and projections for
growth of the market based on trends stakeholders have observed.
Specifically, DOE requests as many years of historical shipments as
can be provided with an example table requested in Table IV.1.
CRAC Issue 21: In order to accurately disaggregate energy
savings by equipment class, DOE is interested in market data by
equipment class, efficiency level, and climatic region.
CRAC Issue 22: DOE requests data and feedback on its methodology
for determining market share by equipment class.
CRAC Issue 23: DOE requests data and feedback on its stock
calculation, particularly data about the number of small data
centers that use CRACs, the assumption that buildings with chiller
or chilled water system will not use CRACs, and any data or
information about the current stock of CRACs.
CRAC Issue 24: DOE seeks input on its determination of the no-
new-standards case distribution of efficiencies for CRACs and its
projection of how amended standards would affect the distribution of
efficiencies in each standards case.
CRAC Issue 25: DOE requests any data or information regarding
whether 15 years is an appropriate average value for CRAC equipment
lifetime and whether equipment lifetime varies based on equipment
class and/or efficiency level.
DOAS Issue 1: DOE requests comment on the approach of evaluating
water-cooled DOASes as a single category (with classes still
disaggregated by those models with energy recovery and those models
without energy recovery) using the specified cooling tower condenser
water entering temperature conditions, and evaluating water-source
heat pump DOASes as a single category (with classes still
disaggregated by those models with energy recovery and those models
without energy recovery) using the specified water-source (rather
than ground-source) inlet fluid temperature conditions.
DOAS Issue 2: DOE requests comment and data on developing a
potential crosswalk from the efficiency levels in ASHRAE 90.1-2016
based on ANSI/AHRI 920-2015 to efficiency levels based on the
revisions to AHRI 920.
DOAS Issue 3: DOE requests information about the ranges of ISMRE
and ISCOP levels that are available on the market by equipment class
and capacity, in order to assist with selection of efficiency
levels, including the market baseline.
DOAS Issue 4: DOE requests comment on the appropriateness of
using the above approach to develop UECs for DOASes, whether
alternative assumptions should be made in the calculations, or
whether an alternate source of DOAS unit energy consumption values
is available. If DOE receives performance data for DOASes, then it
will derive UECs by matching building loads to DOAS performance.
DOAS Issue 5: DOE requests data from field studies and
laboratory testing which show system performance curves and how
capacity and efficiency vary with outdoor air temperature, heating/
cooling load, ventilation load, and any other factors that impact
capacity and efficiency.
DOAS Issue 6: DOE seeks historical data on DOAS shipments and
forecasted growth of DOAS shipments by efficiency level, equipment
class, and capacity.
DOAS Issue 7: DOE seeks information about the most common kinds
of local, in-space cooling system with which a DOAS is paired. DOE
seeks comment on the assumption that DOAS shipments will grow in
line with VRF multi-split systems and water-source heat pumps in
future years.
DOAS Issue 8: DOE also seeks input on how best to determine the
no-standards-case efficiency distribution for DOASes.
DOAS Issue 9: DOE seeks historical shipment-weighted efficiency
data for DOASes by equipment class.
DOAS Issue 10: DOE requests any data or information about the
lifetime of DOASes and whether the equipment lifetime varies based
on equipment class, condenser type, capacity, and efficiency level.
In the absence of data about the lifetime of DOASes, DOE requests
comment on the appropriateness of applying the lifetime developed
for the January 2016 CUAC-CUHP CWAF DFR.
VI. Approval of the Office of the Secretary
The Secretary of Energy has approved publication of this notice of
data availability and request for information.
Signed in Washington, DC, on August 16, 2019.
Alexander N. Fitzsimmons,
Acting Deputy Assistant Secretary for Energy Efficiency, Energy
Efficiency and Renewable Energy.
[FR Doc. 2019-19050 Filed 9-10-19; 8:45 am]
BILLING CODE 6450-01-P