[Federal Register Volume 89, Number 51 (Thursday, March 14, 2024)]
[Proposed Rules]
[Pages 18555-18578]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2024-05462]
========================================================================
Proposed Rules
Federal Register
________________________________________________________________________
This section of the FEDERAL REGISTER contains notices to the public of
the proposed issuance of rules and regulations. The purpose of these
notices is to give interested persons an opportunity to participate in
the rule making prior to the adoption of the final rules.
========================================================================
Federal Register / Vol. 89, No. 51 / Thursday, March 14, 2024 /
Proposed Rules
[[Page 18555]]
DEPARTMENT OF ENERGY
10 CFR Part 431
[EERE-2017-BT-STD-0009]
RIN 1904-AD79
Energy Conservation Program: Energy Conservation Standards for
Walk-In Coolers and Freezers
AGENCY: Office of Energy Efficiency and Renewable Energy, Department of
Energy.
ACTION: Notification of data availability and request for comment.
-----------------------------------------------------------------------
SUMMARY: On September 5, 2023, the U.S. Department of Energy (``DOE'')
published a notice of proposed rulemaking (``NOPR''), in which DOE
proposed amended energy conservation standards for walk-in coolers and
walk-in freezers (``September 2023 NOPR''). In this notification of
data availability (``NODA''), DOE is updating portions of its analysis
for walk-in coolers and walk-in freezers based on information DOE
received in response to DOE's September 2023 NOPR. DOE requests
comments, data, and information regarding the updated analysis.
DATES: DOE will accept comments, data, and information regarding this
NODA no later than April 15, 2024.
ADDRESSES: Interested persons are encouraged to submit comments using
the Federal eRulemaking Portal at www.regulations.gov under docket
number EERE-2017-BT-STD-0009. Follow the instructions for submitting
comments. Alternatively, interested persons may submit comments,
identified by docket number EERE-2017-BT-STD-0009, by any of the
following methods:
(1) Email: [email protected]. Include the docket number
EERE-2017-BT-STD-0009 in the subject line of the message.
(2) Postal Mail: Appliance and Equipment Standards Program, U.S.
Department of Energy, Building Technologies Office, Mailstop EE-5B,
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.
No telefacsimiles (``faxes'') will be accepted. For detailed
instructions on submitting comments and additional information on this
process, see section III of this document.
Docket: The docket for this activity, which includes Federal
Register notices, comments, and other supporting documents/materials,
is available for review at www.regulations.gov. All documents in the
docket are listed in the www.regulations.gov index. However, not all
documents listed in the index may be publicly available, such as
information that is exempt from public disclosure.
The docket web page can be found at www.regulations.gov/docket/EERE-2017-BT-STD-0009. The docket web page contains instructions on how
to access all documents, including public comments, in the docket. See
section III of this document for information on how to submit comments
through www.regulations.gov.
FOR FURTHER INFORMATION CONTACT:
Mr. Troy Watson, 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. Email:
[email protected].
Mr. Matthew Schneider, U.S. Department of Energy, Office of the
General Counsel, GC-33, 1000 Independence Avenue SW, Washington, DC
20585-0121. Telephone: (240) 597-6265. Email:
[email protected].
For further information on how to submit a comment, review other
public comments and the docket, or participate in the public meeting,
contact the Appliance and Equipment Standards Program staff at (202)
287-1445 or by email: [email protected].
SUPPLEMENTARY INFORMATION:
Table of Contents
I. Background
II. Discussion
A. Engineering Analysis
1. Non-Display Doors
a. Maximum Daily Energy Consumption Allowances for Non-Display
Doors With Certain Electrical Components
b. Adjustment of U-Factors and Resulting Thermal Load
2. Dedicated Condensing Units and Single-Packaged Dedicated
Systems
a. More Efficient Single Speed Compressors
b. Off-Cycle Ancillary Power
c. Low GWP Refrigerant Transition
d. Miscellaneous Updates to the Engineering Analysis Spreadsheet
3. Unit Coolers
a. Cost Assumptions at Max-Tech Efficiency Levels
b. Unit Cooler Fan Power
c. Miscellaneous Updates to the Unit Cooler Analysis
B. Trial Standard Levels
1. Refrigeration Systems
2. Non-Display Doors
C. Analytical Results
1. Life-Cycle Cost and Payback Period Analysis
a. Application of the Low-GWP Refrigerant Transition to Specific
Regions
b. Results for Refrigeration Systems
c. Results for Non-Display Doors
2. National Impacts Analysis
a. Non-Display Doors
b. Significance of Energy Savings
c. Net Present Value of Consumer Costs and Benefits
D. Updated Equations for Proposed Standards
1. Energy Consumption Equations for Non-Display Doors
2. AWEF2 Equations
III. Public Participation
IV. Approval of the Office of the Secretary
I. Background
The Energy Policy and Conservation Act, Public Law 94-163, as
amended (``EPCA''),\1\ authorizes DOE to regulate the energy efficiency
of a number of consumer products and certain industrial equipment. (42
U.S.C. 6291-6317) Title III, Part C of EPCA,\2\ established the Energy
Conservation Program for Certain Industrial Equipment. (42 U.S.C. 6311-
6317) Such equipment includes walk-in coolers and walk-in freezers \3\
(hereafter referred to
[[Page 18556]]
as ``walk-ins'' or ``WICFs''), the subject of this rulemaking.
---------------------------------------------------------------------------
\1\ All references to EPCA in this document refer to the statute
as amended through the Energy Act of 2020, Public Law 116-260 (Dec.
27, 2020), which reflect the last statutory amendments that impact
Parts A and A-1 of EPCA.
\2\ For editorial reasons, upon codification in the U.S. Code,
Part C was re-designated Part A-1.
\3\ Walk-in coolers and walk-in freezers are defined as an
enclosed storage space, including but not limited to panels, doors,
and refrigeration systems, refrigerated to temperatures,
respectively, above, and at or below 32 degrees Fahrenheit that can
be walked into, and has a total chilled storage area of less than
3,000 square feet; however, the terms do not include products
designed and marketed exclusively for medical, scientific, or
research purposes. 10 CFR 431.302.
---------------------------------------------------------------------------
DOE defines ``walk-ins'' as an enclosed storage space, including
but not limited to panels, doors, and refrigeration systems,
refrigerated to temperatures, respectively, above, and at or below 32
degrees Fahrenheit that can be walked into, and has a total chilled
storage area of less than 3,000 square feet; however, the terms do not
include products designed and marketed exclusively for medical,
scientific, or research purposes. 10 CFR 431.302. Rather than
establishing standards for complete walk-in systems, DOE has
established standards for the principal components that make up a walk-
in (i.e., doors, panels, and refrigeration systems).
On September 5, 2023, DOE published a notice of proposed rulemaking
(``NOPR'') in the Federal Register regarding energy conservation
standards for walk-in coolers and freezers (``September 2023 NOPR'').
88 FR 60746. Specifically, DOE proposed amended standards for walk-in
non-display doors and walk-in refrigeration systems. DOE did not
propose to amend the standard for walk-in panels or display doors. For
walk-in refrigeration systems, DOE proposed amended standards in terms
of the newly adopted annual walk-in energy factor 2 (``AWEF2'')
metric.\4\ The technical support document (``TSD'') that presented the
methodology and results of the September 2023 NOPR analysis
(``September 2023 NOPR TSD'') is available at www.regulations.gov/document/EERE-2017-BT-STD-0009-0046. Additionally, on September 28,
2023, DOE published a notification of data availability (``September
2023 NODA'') summarizing additional comments received on the June 2022
Preliminary Analysis (87 FR 39008) that were considered but not
discussed in the September 2023 NOPR. 88 FR 66710.
---------------------------------------------------------------------------
\4\ DOE adopted the AWEF2 metric in a test procedure final rule
published on May 4, 2023. 88 FR 28780.
---------------------------------------------------------------------------
On September 27, 2023, DOE held a public webinar (``September 2023
Public Webinar'') in which it presented an overview of the topics
addressed in the September 2023 NOPR, allowed time for prepared general
statements by participants, and encouraged all interested parties to
share their views on issues affecting this rulemaking.
In response to the September 2023 NOPR, DOE received additional
data and information regarding walk-in non-display doors and
refrigeration systems, which is summarized in sections II.A and II.D.2
of this document.
Upon consideration of the views shared in the September 2023 Public
Webinar and public comments DOE received in response to the September
2023 NOPR, this NODA presents updated analysis for walk-in non-display
doors and refrigeration systems. DOE is requesting comments, data, and
information regarding the updated analysis.
DOE notes that it is continuing to consider all of the stakeholder
comments received in response to the September 2023 NOPR and September
2023 Public Webinar in further development of the rulemaking. As
discussed in the September 2023 NOPR, based on consideration of all of
the public comments received, DOE may adopt energy efficiency levels
that are either higher or lower than the proposed standards, or some
combination of level(s) that incorporate the proposed standards in
part.
II. Discussion
In the following sections, DOE details its updated analysis for
walk-in non-display doors and refrigeration systems.
A. Engineering Analysis
1. Non-Display Doors
a. Maximum Daily Energy Consumption Allowances for Non-Display Doors
With Certain Electrical Components
In the September 2023 NOPR, DOE assumed for its analysis that
baseline non-display doors had 3.5-inch-thick insulation for coolers
and 4-inch-thick insulation for freezers, wood framing materials, a
viewing window, and anti-sweat heat around the perimeter of the door
leaf without controls. 88 FR 60746, 60769. DOE did not consider
lighting or other electrical components in its baseline representative
units for non-display doors. Id. As such, DOE only considered design
options relevant to the design of the baseline representative units,
including: anti-sweat controls, reduced anti-sweat heat, improvements
to the framing systems to make the frame more thermally insulative, and
increased insulation thickness. Id. at 88 FR 60770.
Kolpak commented that while it agrees with providing limits on door
components, it disagrees with the overall formulas representing the
proposed energy conservation standards for manual non-display doors.
(Kolpak, No. 66, Attachment 1 at pp. 1, 3) \5\ Kolpak stated that its
basic models are fully compliant with DOE's current regulations, but
that it believes the new proposed maximum daily energy consumption
(``MDEC'') formulas are impossibly stringent. (Kolpak, No. 66,
Attachment 1 at p. 1) Kolpak stated that when considering all
electricity-consuming devices that are installed on its doors,
including the anti-sweat heater wire, door light, heated ventilator,
heated viewing window, and thermometer/temperature alarms, the proposed
standards would not be able to be met. (Id.) Kolpak provided
calculations of the daily energy consumption of six different doors for
both cooler and freezer applications to support their comment. (Kolpak,
No. 66, Attachment 2)
---------------------------------------------------------------------------
\5\ The parenthetical reference provides a reference for
information located in the relevant docket for this rulemaking,
which is maintained at www.regulations.gov. The references are
arranged as follows: (commenter name, comment docket ID number,
attachment number (if there are multiple attachments in a single
comment submission), page of that document).
---------------------------------------------------------------------------
The test procedure for non-display doors requires the direct and
indirect electrical energy consumption of electrical components be
calculated and included in the determination of daily energy
consumption (``DEC'') using rated power of electrical components sited
on the door and an assumed percent time off (``PTO'') value. As
previously mentioned, in the September 2023 NOPR, DOE only considered
one electrical component (i.e., the anti-sweat heat around the
perimeter of the door leaf) in its representative units of manual non-
display doors for the engineering analysis. DOE also considered motors
in its representative units of motorized non-display doors. However,
DOE understands that other electricity-consuming devices could be
installed on a non-display door, which are included in the calculation
of DEC per the test procedure. As indicated by Kolpak in its comment,
the current MDEC standards allow for additional electrical components
such as heated vents, heated viewing windows, lights, and thermometer/
temperature alarms to be included and considered in the DEC
calculation. However, the basis of the proposed energy conservation
standards only accounts for the energy consumption from anti-sweat heat
around the perimeter of the door (and motors for doors classified as
motorized non-display doors). As a result, DOE understands that the
proposed standards as outlined in the September 2023 NOPR may be
difficult to meet for basic models of doors that have
[[Page 18557]]
additional electrical components beyond what DOE considered in its
representative units.
Also in response to the September 2023 NOPR, Senneca and Frank Door
commented that DOE's method for complying with the new standards
presume that all doors have certain features (e.g., lights) that can be
adjusted to consume less energy, but that many doors do not have these
features; thus, Senneca and Frank Door commented that DOE cannot
conclude that new standards are technologically feasible by pointing to
methods for compliance with the standards that are not available for
all classes, types, and sizes of doors. (Senneca and Frank Door, No. 78
at p. 3) DOE notes that for the September 2023 NOPR analysis, DOE did
not consider lighting in its baseline representative units, and
therefore did not consider any design options for reducing lighting
energy consumption in the analysis. However, as indicated by Senneca
and Frank Door, DOE recognizes that it cannot include all other
possible electrical components in its baseline representative units and
cannot analyze reduced energy consumption for other electrical
components because not all doors contain these components.
In light of these comments, DOE is considering equipment classes
with maximum daily energy consumption allowances for non-display doors
if manufacturers offer basic models with certain electricity-consuming
devices as discussed in the following sections. This is similar to the
approach used for the energy conservation standards for consumer
refrigerators, refrigerator-freezers, and freezers. In a direct final
rule relating to energy conservation standards for refrigerators,
refrigerator-freezers, and freezers published on January 17, 2024, DOE
established separate standards and separate product classes for
products with multiple doors or specialty doors. The standards for
those product classes (i.e., any product classes that implement special
and multi-door designs) include energy allowances (i.e., specific
increases in maximum allowable energy use) corresponding to the
specific performance-related features (i.e., door-in-door designs,
transparent doors, and multi-door designs). 89 FR 3026, 3028-3029.
To develop the maximum daily energy consumption allowances specific
for walk-in non-display doors with certain electrical components, DOE
reviewed the data and calculations submitted by Kolpak, as well as
product literature from hardware and instrument manufacturers. In its
comment, Kolpak provided information regarding the following components
that are included on its basic models of non-display doors: anti-sweat
heat on viewing windows; lighting and mechanisms to turn the lighting
on or off (e.g., manual toggle switches, door open timers, occupancy
sensors); heated ventilators (also called heated pressure relief
vents); and temperature alarms. (Kolpak, No. 66, Attachment 1 at pp. 1-
2) Kolpak provided information on model numbers of electrical
components, rated wattage of those components, number of electrical
components on its doors, and the calculation of the direct and indirect
electrical energy consumption for all electrical components. (Kolpak,
No. 66, Attachment 2) Using the detail provided by Kolpak, DOE also
looked into the hardware and instrument manufacturers product offerings
for electrical components to better understand the range of potential
options for these additional electrical components. Based on this, DOE
grouped the electrical components into four categories: lighting, anti-
sweat heat for viewing windows, digital temperature displays/alarms,
and heated pressure relief vents. The underlying assumptions for each
category of electrical components are described in the paragraphs that
follow.
Lighting
For the lighting category, DOE considered lighting, a night light,
and a pilot light located on a switch to develop an appropriate DEC
allowance for doors that have lighting. Lighting features provide
valuable utility to consumers, namely visibility within the walk-in,
particularly near the entrance and exit of the walk-in and is commonly
controlled by a switch. Switches used for turning the lights on and off
often have a pilot light so that the switch can be located in the dark.
Additionally, as included in Kolpak's comment and calculations, a night
light could also be attached to the walk-in door. Based on Kolpak's
provided data and a review of product literature, DOE assumed lighting
would have rated power of 13 W, a switch with a pilot light would have
a rated power of 0.3 W, and a night light would have a rated power of 1
W. DOE also assumed that these components would not be controlled by
some demand-based controls, and therefore used the PTO values specified
for lighting and other electricity-consuming devices without controls,
timers, or auto-shut-off systems per table A.2 of appendix A along with
the rated power to determine the direct electrical energy consumption.
DOE assumed based on a review of product literature and doors it has
tested that the light and night light would be located on the interior
of the walk-in, and the switch may be located either interior or
exterior to the walk-in. Therefore, all of the three components
associated with lighting were conservatively assumed to be sited on the
internal face of the door for the purposes of determining the indirect
electrical energy consumption. See 10 CFR part 431, subpart R, appendix
A, sections 6.3.2.2 and 6.3.3. Based on these assumptions, DOE
calculated the MDEC allowances (i.e., the sum of the direct and
indirect electrical energy consumption) for doors with lighting
components which can be found in Table II.1. DOE notes that the
lighting MDEC allowance would apply to doors with a light that may also
have a night light and/or switch. Therefore, a door does not need to be
equipped with all three components to use the allowance (i.e., a door
with a light and a switch but no nightlight could use the allowance
specified in Table II.1).
Anti-Sweat Heater for Viewing Window
As previously mentioned, DOE included windows in its representative
units of non-display doors. However, DOE did not consider additional
anti-sweat heat specific to the window. Anti-sweat heaters are a
performance-related feature used on viewing windows to prevent (1)
condensation from collecting on the glass and (2) fogging of the glass.
Kolpak commented that it is standard for medium-temperature non-display
doors with viewing windows to have an anti-sweat heater wire around the
frame of the window and for low-temperature non-display doors with
viewing windows to have an anti-sweat heater wire and heated glass
coating on the outer pane of glass. Kolpak commented that the widely
used supplier used to provide a 10 W/ft anti-sweat heater wire without
controls. Kolpak stated that it uses a 5 W/ft heater wire with controls
in the frame of the viewport window. Kolpak stated that it cannot find
additional means to reduce the energy consumption of the anti-sweat
heater wire in the viewing window frame further. (Kolpak, No. 66 at p.
1) Based on Kolpak's provided data and a review of product literature,
DOE assumed that if anti-sweat heat is included around and/or on
viewing windows, that anti-sweat heat would have rated power of 34 W
for medium-temperature (i.e., cooler) applications and 84 W for low-
temperature (i.e., freezer) applications. DOE also assumed that these
components would be controlled by some demand-based controls based on
the information provided by Kolpak, and therefore DOE used the PTO
values specified for anti-sweat heat with
[[Page 18558]]
controls, timers, or auto-shut-off systems per table A.2 of appendix A
along with the rated power to determine the direct electrical energy
consumption. DOE assumed that for the purposes of determining the
indirect electrical energy consumption of the anti-sweat heater, 75-
percent of the total power is attributed to the interior and 25-percent
of the total power is attributed to the exterior of the walk-in,
consistent with the assumptions outlined in the DOE test procedure. See
10 CFR part 431, subpart R, appendix A, sections 6.3.2.2 and 6.3.3.
Based on these assumptions, DOE calculated the MDEC allowance (i.e.,
the sum of the direct and indirect electrical energy consumption) for
doors with anti-sweat heat on their viewing windows, which can be found
in Table II.1.
Digital Temperature Displays With or Without Alarms
A digital temperature display provides utility in that it allows
for users to easily monitor the temperature of the walk-in. The digital
temperature display is connected to a thermocouple that measures the
temperature of the walk-in and the interface on the exterior of the
walk-in displays the temperature within the walk-in compartment. Based
on review of product literature and Kolpak's data, DOE has determined
that a digital temperature display could be paired with alarms or be
standalone (i.e., without alarms). The alarms alert kitchen staff or
others if the refrigerated goods within the walk-in compartment are in
conditions that are too warm or too cold, which may spoil or ruin these
goods. Additionally, alarms can sound if the walk-in door is left open
for too long. Kolpak commented that walk-ins with multiple compartments
that have only one exterior door but have doors on interior partitions
that separate the compartments often have two temperature alarms on the
exterior door so that the alarms can be heard by those outside of the
walk-in. (Kolpak, No. 6, Attachment 1 at p. 2) Kolpak stated that the
temperature alarm is typically rated at 4 W and Kolpak is unable to
source a temperature alarm that has a lower rated power. (Id.)
Additionally, through its review of hardware and instrument
manufacturers product offerings, DOE identified that a panic or
entrapment alarm could be installed for use in the event that a user is
unable to exit the walk-in. Based on Kolpak's provided data and a
review of hardware manufacturer product literature, DOE assumed a
digital temperature display without alarms would have a rated power of
2.4 W and a digital temperature display with alarms would have rated
power of 4 W. In consideration of Kolpak's comment that a walk-in
comprised of two compartments may require two temperature displays with
alarms to be located on the exterior non-display door, DOE assumed that
a digital temperature display with alarm(s) would have a total rated
power of 8 W i.e., to reflect two digital temperature displays with
alarms at 4 W each; an alternative approach could account for the power
multiplied by the number of temperature displays with alarms present in
the walk-in). DOE assumed based on a review of Kolpak's data and
product literature that the digital temperature display with or without
alarms would always be on, and as such used the PTO specified for other
electricity-consuming devices without controls, timers, or auto-shut-
off systems per table A.2 of appendix A along with the rated power to
determine the direct electrical energy consumption. The temperature
display and alarms would likely be sited on the exterior of the walk-in
door to be seen and heard, however, components of the display would be
located interior to the walk-in, such as the thermocouple. Therefore,
DOE conservatively assumed these components would be sited on both the
internal and external face of the door for the purposes of determining
the indirect electrical energy consumption. See 10 CFR part 431,
subpart R, appendix A, sections 6.3.2.2 and 6.3.3. Based on these
assumptions, DOE calculated the MDEC allowances (i.e., the sum of the
direct and indirect electrical energy consumption) for doors with a (1)
digital temperature display without an alarm or (2) digital temperature
display with alarms. These calculated MDEC allowances can be found in
Table II.1. DOE assumed that a door would either have one or the other,
but would not have both (1) a digital temperature display without an
alarm or (2) digital temperature display with alarms. As such, only one
of these MDEC allowances would apply based on whether there is or is
not an alarm connected to the digital temperature display.
Heated Pressure Relief Vent
Heated ventilators, or heated pressure relief vents, are
performance-related features that allow doors to open more easily when
there is a pressure differential between the interior and the exterior
of the walk-in. Kolpak commented that heated ventilators were not
considered in DOE's analysis of non-display doors. Kolpak stated that
some manufacturers put heated ventilators on a non-door panel so that
they are not considered in the energy consumption calculation of a
door, however, Kolpak places these devices on the door, where its
energy consumption is captured in the daily energy consumption
calculation. Kolpak commented that it uses the lowest wattage heated
ventilator available. (Kolpak, No. 66 at p. 2) Kolpak's data indicates
that a 4 W heated ventilator is used on doors for both medium-
temperature and low-temperature installations. DOE has tentatively
determined, however, that while medium-temperature applications may
require a pressure relief vent, it may not be necessary for the
pressure relief vent to be heated. Therefore, DOE did not develop a
MDEC allowance for medium-temperature non-display doors. Additionally,
based on review of hardware manufacturer product literature and the
recommendations for pressure relief vents based on the size of a walk-
in, DOE has tentatively determined that a heated pressure relief vent
for a freezer could require up to 23 W of heat to prevent freezing and
therefore provide sufficient airflow between the walk-in compartment
and the exterior. DOE assumed based on a review of Kolpak's data and
product literature that the heater component of the pressure relief
vent would always be on, and as such used the PTO specified for other
electricity-consuming devices without controls, timers, or auto-shut-
off systems per table A.2 of appendix A along with the rated power to
determine the direct electrical energy consumption. Because the heated
vent is located between both the exterior and interior of the walk-in,
it is considered to be located interior to the walk-in for the purposes
of determining the indirect electrical energy consumption. See 10 CFR
part 431, subpart R, appendix A, sections 6.3.2.2 and 6.3.3. The MDEC
allowance for low-temperature doors with heated pressure relief vents
can be found in Table II.1.
Components Summary
Table II.1 presents the MDEC allowances for lighting, anti-sweat
heat for viewing windows, digital temperature displays/alarms, and
heated pressure relief vents, as described in the previous sections.
[[Page 18559]]
Table II.1--Maximum Daily Energy Consumption Allowances and Assumptions for Each Component
----------------------------------------------------------------------------------------------------------------
MDEC MDEC
Wattage of allowance-- allowance--
Device component(s) Controls (Y/N) Location medium- low-
(W) temperature temperature
(kWh/day) (kWh/day)
----------------------------------------------------------------------------------------------------------------
Door light, night light, and/or 14.3 No............. Interior...... 0.33 0.40
switch.
Heated viewing window: Cooler 34 Yes............ Interior...... 0.25 ..............
Freezer.
Heated viewing window--freezer. 84 Yes............ Interior...... .............. 1.42
Digital temperature without 2.4 No............. Interior...... 0.07 0.09
alarm.
Digital temperature display 8 No............. Interior...... 0.24 0.30
with alarm.
Heated vent--freezer only...... 23 No............. Interior...... .............. 0.85
----------------------------------------------------------------------------------------------------------------
As discussed in the preceding paragraphs, each of these electrical
components provide some consumer utility when installed on a non-
display door. Additionally, having these electrical components
installed on the door limits the number of electrical connections that
need to be wired when installing a walk-in. Pursuant to EPCA, DOE may
establish separate standards for a group of covered equipment (i.e.,
establish a separate equipment class) if DOE determines that separate
standards are justified based on the type of energy used or if DOE
determines that the equipment's capacity or other performance-related
feature justifies a different standard. (42 U.S.C. 6316(a); 42 U.S.C.
6295(q)(1)(B)) DOE has tentatively determined that that the devices it
has listed previously constitute a performance-related feature that
justify a higher standard. DOE notes that the information described
previously and in Table II.1 was used to develop the MDEC allowances
for basic models of non-display doors that have any number of these
components. However, DOE notes that for the purposes of determining DEC
in accordance with the Federal test procedure at appendix A,
manufacturers must follow the instructions for calculating both direct
and indirect electrical energy consumption of components as described
in appendix A.
DOE reviewed non-public manufacturer data submitted to DOE's
Compliance Certification Management System Database (``CCD'') to
estimate the percentage of the market that includes these other
electricity consuming devices on non-display doors. DOE's estimates of
shipments containing electricity consuming devices are shown in Table
II.2.
Table II.2--Percentage of Non-Display Door Shipments Containing Each Electricity Consuming Device
----------------------------------------------------------------------------------------------------------------
Percent of shipments with component
---------------------------------------------------------------
Component Medium- Low- Medium- Low-
temperature, temperature, temperature, temperature,
manual (%) manual (%) motorized (%) motorized (%)
----------------------------------------------------------------------------------------------------------------
Lighting........................................ 10 6 22 33
Viewing Window ASH.............................. 4 1 4 3
All Other Electrical Components................. 8 8 28 73
----------------------------------------------------------------------------------------------------------------
DOE requests comment on the MDEC allowances for the specified
electricity consuming devices. Additionally, DOE requests comment on
the assumed wattages, presence or absence of controls, and location
that were considered in the calculation of MDEC allowances for the
specified electricity consuming devices.
The analytical results (i.e., LCC, PBP, and NIA) presented in
section II.C of this document account for the updates discussed in this
section.
b. Adjustment of U-Factors and Resulting Thermal Load
The DOE test procedure requires that the total non-display door
energy is calculated by summing (1) the total daily energy consumption
due to thermal conduction load through the door (i.e., the additional
refrigeration energy consumption to overcome conduction through the
door), (2) total daily direct electrical energy consumption (i.e., the
energy consumed by electrical components sited on the door), and (3)
the total daily indirect electrical energy consumption (i.e., the
additional refrigeration energy consumption due to thermal output into
the walk-in from electrical components contained on the inside face of
the door). See 10 CFR part 431, subpart R, appendix A, section 6.3.4.
The energy consumption due to thermal conduction load is based on an
assumed temperature difference between the interior and exterior of the
walk-in, an assumed refrigeration system energy efficiency ratio
(``EER''), and the U-factor and size of the door. Improvements to the
design and/or materials of the door and its frame could result in a
decreased thermal load.
At the proposed standard level in the September 2023 NOPR, DOE
assumed that all manual-opening non-display doors would need to
implement anti-sweat heater controls, improved framing systems, and
reduced anti-sweat heat. 88 FR 60746, 60845. As discussed in the
September 2023 NOPR TSD, DOE determined U-factors for each
representative door size by scaling the U-factors determined from
tested non-display doors based on theoretical U-factors. DOE also
assumed each non-display door had a window sized at 2 ft\2\. Wood
frames are the least efficient framing material currently found on the
market and were selected as the baseline framing material. High-density
polyurethane door frames are more thermally insulative and were
selected as the improved framing material. See section 5.7.1.3 of the
September NOPR TSD. In response to the September 2023 NOPR, Kolpak
commented that it uses low-density, high-insulation foam core material
in its frame, which has better insulation than wood or high-density
[[Page 18560]]
foam. (Kolpak, No. 66 at p. 2) Therefore, DOE would expect that the
thermal load at the proposed level to be consistent with or greater
than the thermal load in the Kolpak data.
In the data provided by Kolpak there are U-factor test results for
both medium-temperature and low-temperature non-display doors of
various sizes with and without a window. (Kolpak, No. 66 Attachment 2)
For medium-temperature doors, DOE found that the thermal conduction
load at the proposed energy conservation standard level from the
September 2023 NOPR is consistent with the thermal conduction load
calculated from the data provided by Kolpak data. For low-temperature
doors, DOE found that the thermal conduction load at the proposed
energy conservation standard level from the September 2023 NOPR was
lower than the thermal conduction load calculated from the data
provided by Kolpak data. To further evaluate thermal conduction load
for both medium-temperature and low-temperature non-display doors, DOE
further reviewed additional non-public manufacturer data submitted to
DOE's Compliance Certification Management System Database (``CCD'').
Manufacturers are not currently required to certify the U-factor or
thermal conduction load to the CCD; however, they are required to
certify the rated power of each light, heater wire, and/or other
electricity consuming device associated with each basic model and
whether such device(s) has a timer, control system, or other demand-
based control reducing the device's power consumption. See 10 CFR
429.53(b)(4)(i). Using the certified data, DOE back-calculated the
thermal load and ultimately U-factor for multiple basic models of
medium-temperature and low-temperature non-display doors. DOE verified
these back-calculated U-factors with its own test data. DOE compared
the thermal conduction load by non-display door area (AND)
of (1) Kolpak's data, (2) any back-calculated data from the CCD that
has been verified with test data, (3) data received during confidential
manufacturer interviews, and (4) test data, with the thermal load by
non-display door area for each representative unit and efficiency level
with a different door construction design (and thus different thermal
conduction load) from the September 2023 NOPR. DOE is posting a
supplementary file that contains supplementary information to support
the analysis provided in this NODA (referred to as the ``NODA support
document'').\6\ The updated thermal conduction load for low-temperature
non-display doors is shown in Figure 4.1 of the NODA support document
that has been posted to the docket. Additionally, the updated energy
consumption values for low-temperature non-display doors that reflect
the U-factor and resulting thermal load update can be found in section
2 of the NODA support document. Note that these energy consumption
values do not account for any of the MDEC allowances.
---------------------------------------------------------------------------
\6\ The NODA support document can be found in the docket at
www.regulations.gov/document/EERE-2017-BT-STD-0009.
---------------------------------------------------------------------------
For low-temperature applications, DOE has tentatively determined
that the thermal conduction load by area for low-temperature
applications in the proposed standard level from the September 2023
NOPR is lower than that calculated using the data DOE evaluated for
this NODA. Therefore, DOE increased the U-factors for each
representative unit of low-temperature non-display doors by 9-percent
for this NODA. DOE has tentatively determined that this increase in U-
factor would be more representative of the low-temperature non-display
doors currently on the market.
DOE requests comment on representativeness of the adjustments made
to the U-factors for the low-temperature non-display doors.
The analytical results (i.e., LCC, PBP, and NIA) presented in
section II.C of this document account for the updates discussed in this
section.
2. Dedicated Condensing Units and Single-Packaged Dedicated Systems
a. More Efficient Single Speed Compressors
In the September 2023 NOPR, DOE analyzed higher-efficiency
compressors for dedicated condensing units and single-packaged
dedicated systems. The higher-efficiency compressor design options
included both higher-efficiency single-speed compressors and variable-
speed compressors. For single-packaged dedicated systems, DOE
considered both higher-efficiency single-speed compressors and
variable-speed compressors in the September 2023 NOPR. However, DOE did
not consider higher-efficiency single-speed compressors for dedicated
condensing units in the September 2023 NOPR. See section 5.7.2.1 of the
September 2023 NOPR TSD for further discussion.
In response to the September 2023 NOPR, the Efficiency Advocates
recommended that DOE analyze improved single-speed compressor
efficiency as a design option. (Efficiency Advocates, No. 77 at p. 2)
The Efficiency Advocates stated that there is a range of single-speed
compressor efficiencies available even when selecting for a given
compressor type, capacity, input voltage, power supply, and
refrigerant. (Id. at p. 2)
The CA IOUs recommended that DOE consider two single-speed
compressor efficiencies (i.e., CMP1 and CMP2) as design options for
dedicated condensing units. (CA IOUs, No. 76 at pp. 8-9) The CA IOUs
stated that the compressor manufacturers Copeland and Bitzer offer two
or three more compressor options with different efficiencies at each
size and temperature application and that therefore CMP1 and CMP2 are
justified as design options. (Id. at pp. 8-9)
In response to the comments received, DOE reviewed publicly
available compressor performance data for both medium-temperature and
low-temperature walk-in applications. DOE specifically collected data
for compressors applicable to the range of representative capacities
analyzed for dedicated condensing units in the September 2023 NOPR.\7\
For this NODA analysis, DOE only considered single-speed compressors
compatible with R-448A that are rated at the DOE walk-in test
conditions and available for the North American walk-in market.\8\ DOE
excluded from consideration any compressors that may negatively impact
consumer utility--e.g., DOE did not consider three-phase compressors
when there were options for both single- and three-phase compressors at
a given capacity, as some buildings where walk-ins are installed may
not have the necessary three-phase power. Additionally, as discussed in
section 5.7.2.1 of the September 2023 NOPR TSD, during interviews
manufacturers highlighted utility concerns related to customer
preference for specific compressor types (e.g., scroll, semi-hermetic,
etc.). Therefore, when evaluating higher-efficiency single-speed
compressors for this NODA, DOE selected the highest compressor
efficiency that would still allow for consumer choice between scroll
and semi-hermetic compressors if both compressor types were available
at the given representative capacity. DOE notes that it cannot verify
that the
[[Page 18561]]
compressor data provided by the CA IOUs and Efficiency Advocates in
their respective comments are representative of compressors rated at
DOE walk-in test conditions. Additionally, the compressors provided may
impact utility because there are both scroll and semi-hermetic types.
Therefore, DOE did not evaluate the compressors provided in the
comments from the CA IOUs and Efficiency Advocates. However, using the
criteria described for reviewing publicly available compressor data,
DOE identified single-speed compressors with capacities roughly between
50 and 60 kBtu/h that have higher efficiencies than the compressor in
that capacity range used in the September 2023 NOPR analysis.
Compressors in this capacity range could be used in the DC.M.O.054,
DC.M.I.054, and DC.M.O.124 representative units.\9\ DOE did not
identify any higher efficiency single-speed compressors for low-
temperature applications at the representative capacities analyzed
based on the criteria previously mentioned.
---------------------------------------------------------------------------
\7\ These capacities are as follows: 9 kBtu/h, 25 kBtu/h, 54
kBtu/h, 75 kBtu/h, and 124 kBtu/h for medium-temperature dedicated
condensing units; 3 kBtu/h, 9 kBtu/h, 54 kBtu/h, 75 kBtu/h for low-
temperature dedicated condensing units.
\8\ For a discussion of DOE's tentative conclusions regarding
the appropriateness of setting standards based upon models operating
with R-448A, see 88 FR 60746, 60771.
\9\ DOE used two compressors with capacities between 50 and 60
kBtu/h for the 124 kBtu/h medium-temperature outdoor dedicated
condensing unit. DOE determined that this would be representative
for units of this capacity.
---------------------------------------------------------------------------
As such, DOE determined that a higher-efficiency single-speed
compressor design option could be applied to the following
representative units: DC.M.O.054, DC.M.I.054, and DC.M.O.124. In this
NODA, DOE presents an updated analysis when considering the additional
compressor design option for these three representative units.
In its updated analysis, DOE added an efficiency level (``EL'')
which corresponds to the higher-efficiency single-speed compressor
design option for the three representative units mentioned previously.
The higher-efficiency single-speed compressor has an EER for walk-in
refrigeration systems of 7.62 Btu/(W-h), which is 5 percent greater
than the baseline compressor's EER of 7.25 Btu/(W-h).\10\ Similar to
the NOPR analysis, DOE ordered the design options for each
representative unit in terms of decreasing cost-effectiveness
(manufacturer production cost differential/AWEF2 differential). Table
3.1 of the NODA support document describes the design option codes
related to the refrigeration system representative units analyzed in
this NODA. The higher-efficiency single-speed compressor was added at
EL 1 for the DC.M.I.054 representative unit and at EL 3 for both
DC.M.O.054 and DC.M.O.124 representative units. As a result, the design
options that are used at ELs after the higher-efficiency single-speed
compressor design option are now associated with one EL higher than in
the September 2023 NOPR. For example, in the September 2023 NOPR,
electronically commutated (``EC'') condenser fan motors were
implemented at EL 1 for the DC.M.I.054 Because the higher-efficiency
single-speed compressor design option was implemented at EL 1 in this
NODA analysis, the EC condenser fan motor design option is implemented
at EL 2 for this representative unit.
---------------------------------------------------------------------------
\10\ DOE determined compressor performance using conditions
representative of the A condition test specified by the DOE test
procedure for walk-in refrigeration systems in appendix C1 to
subpart R of 10 CFR part 431. The test conditions used to determine
compressor performance were as follows: a return gas temperature of
41 [deg]F, an evaporator dewpoint temperature of 23 [deg]F, and a
condenser dewpoint temperature of 120 [deg]F.
---------------------------------------------------------------------------
Section 3 of the NODA support document shows the cost-efficiency
results from the September 2023 NOPR, which were published in appendix
5A of the September 2023 NOPR TSD,\11\ and the updated cost-efficiency
results with the additional compressor design option EL. The tables
show the AWEF2, manufacturer production cost (``MPC''), and
manufacturer selling price (``MSP'') plus shipping costs associated
with each EL. DOE notes that due to the interaction between design
options in the engineering analysis, the performance increase and/or
incremental MPC associated with design options added after the higher-
efficiency single-speed compressor design option differ from those
presented in the NOPR analysis.
---------------------------------------------------------------------------
\11\ DOE notes that in appendix 5A of the September 2023 NOPR
TSD, the tables label the efficiency values in terms of AWEF,
however, they are in terms of AWEF2 and should have been labeled as
such.
---------------------------------------------------------------------------
DOE requests comment on the updated cost-efficiency results for the
54 kBtu/h indoor and outdoor medium-temperature dedicated condensing
units and 124 kBtu/h outdoor medium-temperature dedicated condensing
unit presented in section 3 of the NODA support document.
The analytical results (i.e., LCC, PBP, and NIA) presented in
section II.C of this document account for the updates discussed in this
section.
b. Off-Cycle Ancillary Power
Based on test data available at the time, in the September 2023
NOPR analysis DOE tentatively determined that the only source of off-
cycle power for dedicated condensing units and single-packaged
dedicated systems would be crankcase heater power. See section 5.6.3.3
of the September 2023 NOPR TSD. DOE assumed that the off-cycle
crankcase heater power would be the same for both medium-temperature
and low-temperature applications, which DOE estimated using crankcase
heater wattage specifications from compressor manufacturer product
literature.
In response to the September 2023 NOPR, AHRI and Hussmann commented
that there are potential sources of off-cycle ancillary power that DOE
did not account for and should consider, such as standard operating
controls, defrost time clocks, digital controllers, and transformers.
(AHRI, No. 72 at p. 19; Hussmann, No. 75 at p. 9)
In response to these comments, DOE analyzed additional test data
and compared the tested off-cycle power values to the crankcase heater
wattages specified by compressor manufacturers. DOE found that for
medium-temperature dedicated condensing units, the assumed crankcase
heater wattage used in the NOPR analysis matched both the tested off-
cycle power values and the compressor manufacturer-specified wattages.
Therefore, DOE has tentatively determined that the assumed crankcase
heater wattages used to analyze medium-temperature dedicated condensing
units and single-packaged dedicated systems in the NOPR analysis are
representative of the entire off-cycle power of such units.
For low-temperature dedicated condensing units, DOE found that the
off-cycle power test data was up to 5 Watts greater than the compressor
manufacturer-specified crankcase heater wattages, indicating there may
be additional sources of off-cycle power other than the crankcase
heater. Additionally for low-temperature units, DOE found that the
compressor manufacturer-specified crankcase heater wattages at a given
capacity range were slightly different than those specified for medium-
temperature units. Therefore, for this NODA, DOE adjusted the assumed
crankcase heater wattages for low-temperature dedicated condensing
units and single-packaged dedicated systems, as shown in table II.2 and
table II.3. DOE also added 5 Watts of off-cycle ancillary power not
associated with crankcase heater power for all low-temperature
dedicated condensing units and single-packaged dedicated systems. Both
changes can be seen in the updated refrigeration engineering analysis
spreadsheet.\12\ As
[[Page 18562]]
indicated by commenters, DOE suspects that this additional 5 Watts of
power is attributed to timers and controls associated with defrost
cycles.
---------------------------------------------------------------------------
\12\ The updated refrigeration systems engineering sheet can be
found in the docket for this rulemaking at www.regulations.gov/docket/EERE-2017-BT-STD-0009.
Table II.3--Crankcase Heater Power (W) for Low-Temperature Refrigeration Systems From September 2023 NOPR
----------------------------------------------------------------------------------------------------------------
Refrigeration system capacity
-------------------------------------------------------------------
Compressor type >=10,000 and >=50,000- >=100,000-
<10,000 Btu/h <50,000 Btu/h <100,000 Btu/h <200,000 Btu/h
----------------------------------------------------------------------------------------------------------------
Hermetic.................................... 40
Scroll...................................... 40 67 90 100
Semi-Hermetic............................... 40 50 70 100
Rotary...................................... 27
----------------------------------------------------------------------------------------------------------------
Table II.4--Updated Crankcase Heater Power (W) for Low-Temperature Refrigeration Systems for This NODA
----------------------------------------------------------------------------------------------------------------
Refrigeration system capacity
-------------------------------------------------------------------
Compressor type >=5,000- >=20,000- >=50,000-
<5,000 Btu/h <20,000 Btu/h <50,000 Btu/h <200,000 Btu/h
----------------------------------------------------------------------------------------------------------------
Hermetic.................................... 40
Scroll...................................... 40 70 73 100
Semi-Hermetic............................... 40 50 70 100
Rotary...................................... 27
----------------------------------------------------------------------------------------------------------------
DOE requests comment on the updated crankcase heater wattages and
additional off-cycle ancillary power for low-temperature dedicated
condensing units and single-packaged dedicated systems.
The analytical results (i.e., LCC, PBP, and NIA) presented in
section II.C of this document account for the updates discussed in this
section.
c. Low GWP Refrigerant Transition
As discussed in the September 2023 NOPR, the Environmental
Protection Agency (``EPA'') published a NOPR, ``Phasedown of
Hydrofluorocarbons: Restrictions on the Use of Certain
Hydrofluorocarbons Under Subsection (i) the American Innovation and
Manufacturing Act of 2020'', on December 15, 2022, as a part of the
American Innovation and Manufacturing (``AIM'') Act, which outlined new
refrigerant regulations regarding acceptable global warming potential
(``GWP'') limits for various air conditioning and refrigeration
systems. 87 FR 76738. On October 24, 2023, EPA finalized these
proposals (``October 2023 AIM Act Final Rule''). 88 FR 73098. The
October 2023 AIM Act Final Rule established (effective January 1, 2026)
a limit of 300 GWP for remote condensing units in retail food
refrigeration systems and cold storage warehouses with less than 200
lbs of charge, which includes split-system walk-in refrigeration
systems covered under the scope of the September 2023 NOPR. 88 FR
73098, 73209. In the September 2023 NOPR, DOE analyzed R-454A and R-
455A refrigerants which have GWPs less than 300 and tentatively
determined that R-454A would be the most likely replacement refrigerant
for medium- and low-temperature walk-in refrigeration systems once the
regulations finalized in the October 2023 AIM Act Final Rule take
effect. DOE also tentatively determined that R-454A would have
comparable performance to the currently-used refrigerant R-448A. 88 FR
60746, 60772. As there was limited compressor performance data
available for R-454A at the time, DOE used R-448A as the basis for its
engineering analysis for medium- and low-temperature dedicated
condensing units and single-packaged dedicated systems.\13\ Id. In the
September 2023 NOPR, DOE requested performance data for walk-in
refrigeration systems using R-454A, R-454C, and/or R-455A. DOE also
sought comment on its tentative determinations that R-454A is the most
likely replacement for the current refrigerants being used (i.e., R-
448A and R-449A) and that walk-in dedicated condensing systems would
not suffer a performance penalty when switching from R-448A or R-449A
to R-454A. Id.
---------------------------------------------------------------------------
\13\ DOE notes that a more efficient single-speed compressor
that used propane was analyzed as a design option for some single-
packaged dedicated systems. A propane compressor was analyzed if the
charge limit for propane was sufficient to provide the analyzed
capacity and the propane compressor resulted in increased
efficiency.
---------------------------------------------------------------------------
In response, AHRI, Lennox, and Hussmann commented that R-454A is
comparable in performance to R-448A but that it is not the most likely
low-GWP replacement for WICFs because R-454A has a GWP above 150.
(AHRI, No. 72 at p. 10; Lennox, No. 70 at pp. 6-7; Hussmann, No. 75 at
p. 10) AHRI and Lennox recommended that modeling should instead be
conducted using R-454C and/or R-455A since California and Washington
state regulations prohibit the use of a refrigerant with a GWP greater
than 150 for systems with more than 50 lbs. of refrigerant charge.
(AHRI, No. 72 at p. 10; Lennox, No. 70 at pp. 6-7) Hussmann and NRAC
commented that there may be some states with stricter regulations than
the EPA that may not allow refrigerants above 150 GWP. (Hussmann, No.
75 at p. 10; NRAC, No. 73 at p. 2)
DOE acknowledges that certain localities already require, or may
require in the future, WICF refrigeration systems to be designed for
use with sub-150 GWP refrigerants.\14\ Based on analysis of low-GWP
refrigerant performance in walk-in refrigeration systems conducted for
the September
[[Page 18563]]
2023 NOPR, DOE has tentatively concluded that the highest performing
sub-150 GWP refrigerant appropriate for use in split-system walk-in
refrigeration systems is R-454C. See section 5.6.3.1 of the September
2023 NOPR TSD. To assess the potential impact of state level sub-150
GWP requirements, DOE reviewed the EERs of R-454C compressors with
capacities representative of walk-in refrigeration systems and compared
these EERs to those of the baseline compressors analyzed in the
September 2023 NOPR. DOE determined the R-454C EERs at operating
conditions representative for the A test conditions prescribed in the
DOE test procedure for walk-in refrigeration systems, adjusting the
condensing dewpoint up 2 [deg]F to account for the higher refrigerant
temperature glide of R-454C as compared to R-448A or R-454A.
---------------------------------------------------------------------------
\14\ California established (effective January 1, 2022) a limit
of 150 GWP for retail food refrigeration equipment and cold storage
warehouses with less than 50 lbs of charge. Washington is expected
to establish a limit of 150 GWP for retail food refrigeration
equipment and cold storage warehouses with less than 50 lbs of
charge.
---------------------------------------------------------------------------
DOE found that trends in the R-454C compressor efficiencies
generally aligned with the compressor EERs used in the September 2023
NOPR analysis, except for the DC.M.O.025 and DC.M.I.025 representative
units. At this 25 kBtu/h capacity DOE found that the available R-454C
compressor had an EER that is 4 percent less than that of the
compressor analyzed in the September 2023 NOPR. Based on this, DOE
determined that using the R-454C compressor analyzed could result in an
AWEF2 that is 2 percent lower for 25 kBtu/h medium-temperature
dedicated condensing units than a comparable unit using an R-454A-
compatible compressor. As such, and in the absence of more efficient
compressors of the same type compatible with R-454C, DOE has
tentatively determined that to achieve the standard proposed in the
September 2023 NOPR (based on the performance of R-448A), a medium-
temperature walk-in refrigeration system using a sub-150 GWP
refrigerant may need to incorporate additional design options beyond
what DOE presumed in the September 2023 NOPR. To determine the cost of
these additional design options DOE constructed the cost curves
corresponding to use of the R-454C compressor (with roughly 2-percent
reduction of AWEF2 for each evaluated design) and calculated additional
cost to attain the proposed AWEF2 by interpolating along the cost-
efficiency curves. Based on this analysis DOE has tentatively
determined that additional MSP required to achieve the proposed AWEF2
for less-than-150 GWP refrigerant would be $381 for 25 kBtu/h medium
temperature indoor dedicated condensing units and $96 for 25 kBtu/h
medium temperature outdoor dedicated condensing units.
DOE requests comment on the estimated additional MPC associated
with 25 kBtu/h medium temperature indoor and outdoor dedicated
condensing units achieving the proposed AWEF2 standard levels while
operating with a refrigerant with less than 150 GWP.
The analytical results (i.e., LCC, PBP, and NIA) presented in
section II.C account for the cost adder presented in this section, as
described in section II.C.1.a of this document.
d. Miscellaneous Updates to the Engineering Analysis Spreadsheet
In response to the September 2023 NOPR, stakeholders commented that
there were several issues with calculations in the refrigeration
systems engineering spreadsheet.\15\ AHRI and Hussmann suggested
several corrections to the engineering spreadsheet. (AHRI, No. 72 at
pp. 17-19; Hussmann, No. 75 at pp. 7-9) DOE also identified several
issues not prompted by comments. DOE discusses the corrections that it
made in this NODA in the following paragraphs. To the extent that
stakeholders made comments on the engineering spreadsheet and DOE has
determined that updates to the spreadsheet are not necessary, DOE will
address those comments in a subsequent rulemaking.
---------------------------------------------------------------------------
\15\ The September 2023 NOPR refrigeration systems engineering
sheet can be found at www.regulations.gov/docket/EERE-2017-BT-STD-0009-0052.
---------------------------------------------------------------------------
AHRI and Hussmann commented that row 77 for the condenser and row
86 for the evaporator on the `Calculation' tab were calculating
pressures at the incorrect point of the refrigeration cycle, claiming
that all subsequent calculations use the wrong pressures. (AHRI, No. 72
at pp. 17-18; Hussmann, No. 75 at pp. 7-8) DOE notes that the
calculations in question are used only for determination of refrigerant
glide to adjust from midpoint to dewpoint. The errors in these
adjustments result in roughly 0.1 [deg]F difference in calculated dew
point temperature for the condenser. They result in zero difference in
evaporator dew point temperature for dedicated condensing unit
calculations (for which evaporator dew point temperature is prescribed
by the test procedure) and roughly 0.03 [deg]F difference for single-
packaged dedicated systems calculations. These differences make no
significant impact on overall results. Nevertheless, DOE has revised
the calculations for this NODA such that the calculation will be based
on a quality of 0.5 for the condenser, which is representative of the
condenser midpoint, and a quality for the evaporator somewhat greater
than 0.5 to account for the fact that evaporator refrigerant inlet
quality is non-zero.
AHRI and Hussmann commented that in rows 165 and 233 of the
`Calculations' tab, which contain the condenser half glide calculation
for B and C conditions, the formula is using a temperature input rather
than a pressure input to calculate a temperature output. (AHRI, No. 72
at pp. 18-19; Hussmann, No. 75 at p. 9). This calculation results in
overestimation of the dew point by roughly 0.5 [deg]F, and a
corresponding slight overestimation of compressor energy use. DOE has
revised this calculation for this NODA.
In the September 2023 NOPR, the cost of additional spark-proofing
electronic components was not properly accounted for due to an
incorrect formula. In the updated refrigeration system engineering
analysis spreadsheet, DOE updated the compressor cost calculation
(which feeds into the MPC) to include the additional costs for spark-
proofing electronic components for single-packaged dedicated systems
that use propane as the refrigerant. As a result of this change in MPC
associated with propane-compatible compressors, DOE reordered the
design options of the SP.M.O.002 and SP.M.I.002 representative units
such that the design options are ordered from most cost-effective AWEF2
improvements to the least cost-effective AWEF2 improvements, where
cost-effectiveness is based on the ratio of AWEF2 increase to MPC
increase.
In the September 2023 NOPR, all the high-temperature, 2 kBtu/h and
7 kBtu/h, outdoor single-packaged dedicated system representative units
implemented the variable-speed condenser fan design option before the
electronically commutated motor design option was implemented. However,
an electronically commutated motor is a prerequisite for the variable-
speed condenser fan design option. In the updated refrigeration system
engineering spreadsheet, DOE reordered the variable-speed condenser fan
and electronically commutated motor design options for these
representative units. DOE notes that reordering these design options
did not impact the results of the proposed efficiency level as both
design options were included in the efficiency level corresponding to
the proposed standard level.
Additionally, DOE updated the calculation of the enthalpy exiting
the unit cooler that is used in the calculation of the gross capacity
for
[[Page 18564]]
dedicated condensing units to be consistent with the DOE test
procedure. See section C7.5.2 of American National Standards Institute/
Air-Conditioning, Heating, and Refrigeration Institute Standard 1250
(I-P), ``2020 Standard for Performance Rating of Walk-in Coolers and
Freezers''. The calculation for the enthalpy exiting the unit cooler
for single-packaged dedicated systems was consistent with the DOE test
procedure for the NOPR analysis and therefore, DOE did not update it
for single-packaged dedicated systems for this NODA.
Overall, the updates made to the engineering analysis spreadsheet
resulted in a minimal change to the cost-efficiency curves for each
representative unit. Comparing efficiency levels with the same design
option combinations for each representative unit between the September
2023 NOPR and this NODA, the AWEF2s generally increased or decreased
between 1- and 3-percent as a result of the changes discussed
previously. Similarly, in this NODA, design option order generally
remained as it was in the NOPR, and manufacturer production costs did
not change from the NOPR for many representative units. However, in
some cases, changes in representative unit performance at the baseline
required re-baselining to meet the current energy conservation
standards. This re-baselining resulted in slightly different
combinations of design options at the baseline efficiency level for the
following representative units, which also resulted in either more or
fewer design options above baseline depending on whether the baseline
efficiency level needed fewer or more design options at the baseline to
meet the current AWEF standards: DC.M.O.009, DC.M.I.025, DC.L.O.075,
and SP.L.I.006. Additionally, some of the changes to the engineering
spreadsheet impacted cost model inputs (e.g., fan motor horsepower
impacts the cost of a fan motor); therefore, there are slight changes
to the manufacturer production costs associated with some
representative units' efficiency levels even if the design option order
has not changed from the September 2023 NOPR analysis. This was the
case for the following representative units: DC.M.O.009, DC.M.O.025,
DC.M.O.054, DC.M.O.075, DC.M.O.124, DC.M.I.009, DC.M.I.025, DC.M.I.054,
DC.M.I.075, DC.L.O.003, DC.L.O.009, DC.L.O.025, DC.L.O.054, DC.L.I.003,
DC.L.I.009, DC.L.I.025, DC.L.I.054, SP.L.O.002, and SP.L.I.002.
See section 3 of the NODA support document for updated cost-
efficiency results. The analytical results (i.e., LCC, PBP, and NIA)
presented in section II.C of this document account for the updates
discussed in this section.
3. Unit Coolers
a. Cost Assumptions at Max-Tech Efficiency Levels
In the September 2023 NOPR, using the Unit Cooler Performance
Database \16\ DOE developed linear cost-efficiency correlations for
each representative unit, which DOE used to determine the MPC increase
from the baseline efficiency level to the higher efficiency levels for
unit coolers. See section 5.8.6 of the September 2023 NOPR TSD. When
building the Unit Cooler Performance Database, DOE did not consider
that adding additional rows to the unit cooler heat exchanger would
require an increase in cabinet size when determining the MPCs
associated with each efficiency level. DOE based this assumption on
manufacturers' unit cooler product catalogs, which included unit cooler
case dimensions.
---------------------------------------------------------------------------
\16\ The Unit Cooler Performance Database can be found at
www.regulations.gov/document/EERE-2017-BT-STD-0009-0064.
---------------------------------------------------------------------------
In response, Lennox stated that increasing 4-row unit cooler
designs to 5- or 6-row designs is not cost-effective because adding
coil rows has diminishing returns on improved efficiency and would
result in increased coil face area and increased cabinet size. (Lennox,
No. 70 at p. 4) AHRI, Hussmann, and Lennox commented that current unit
cooler coil and cabinet designs are optimized around 4-row designs and
increasing efficiency would be more costly than what DOE estimated when
considering packaging, freight, materials, and scrap. (AHRI, No. 72 at
pp. 3-4, 9; Hussmann, No. 75 at pp. 2, 12; Lennox, No. 70 at p. 4) \17\
---------------------------------------------------------------------------
\17\ DOE notes that it also received comments indicating that
the conversion costs for refrigeration systems should be
incorporated as an amortized consideration in the MSP. DOE will
consider and address these stakeholder comments in a subsequent
rulemaking.
---------------------------------------------------------------------------
During the development of the September 2023 NOPR analysis, DOE
identified several manufacturers producing unit coolers with heat
exchangers 5 or more rows deep. However, DOE acknowledges the concerns
of AHRI, Lennox, and Hussmann that some manufacturers may not be
currently producing unit coolers with heat exchangers 5 rows deep. As
such, these manufacturers may need to expand the cabinet size of their
4-row unit coolers to accommodate larger heat exchangers (i.e.,
evaporator coils with at least 5 rows). In response to this feedback,
DOE updated its analysis for this NODA and assumed that the unit cooler
case would have to be expanded to accommodate an additional row at the
maximum technology (``max-tech'') efficiency level for every unit
cooler representative unit.
DOE estimated the additional MPC using the same cost modeling
processes described in section 5.4 of the September 2023 NOPR TSD. The
additional MPC includes additional material, scrap, and packaging
associated with the cabinet size increase. DOE developed this
additional MPC for expanding unit cooler case size for several
representative units. The average cost adder associated with the
cabinet size increase was $11 for the representative capacities DOE
analyzed. Updated unit cooler cost efficiency curves can be found in
section 3 of the NODA support document.
DOE has tentatively determined that the increase in shipping cost
would not significantly affect the analysis and therefore, did not
include this in the revised analysis in this NODA.
The analytical results (i.e., LCC, PBP, and NIA) for unit coolers
presented in section II.C of this document account for the updates
discussed in this section.
b. Unit Cooler Fan Power
As discussed in section 5.5.4.2 of the September 2023 NOPR TSD, DOE
used unit cooler fan powers from manufacturer product catalogs to
construct the Unit Cooler Performance Database. In general, DOE found
that the fan powers reported in product catalogs were constant across
unit cooler models that only appeared to differ in the number of rows
in their heat exchangers. Further, fan motor powers per fan were the
same across families of unit coolers having the same general geometry
and fan diameter, where the unit coolers differed only by overall unit
cooler length (and number of fans) and number of tube rows in the
evaporator. As such, DOE assumed for the NOPR analysis that unit cooler
fan power would not change when additional heat exchanger rows were
added.
Lennox stated that adding additional rows would have diminishing
performance returns for several reasons including that higher fan power
is needed to maintain airflow when additional coil depth is added due
to the additional pressure drop imposed by the added tube rows.
(Lennox, No. 70 at p. 4)
Increasing heat exchanger size by adding a row could increase the
internal static pressure (``ISP'') that the unit cooler fan would need
to overcome and would therefore require more fan power to maintain the
same airflow at a higher
[[Page 18565]]
ISP. DOE notes that when unit cooler airflow is reported in product
catalogs for models that only appear to differ in number of heat
exchanger rows, the airflow generally decreases when an additional heat
exchanger row is added, but (as previously noted) the fan power listed
stays constant. To quantify the potential increase in fan power, DOE
estimated the increase in ISP associated with adding additional heat
exchanger rows using CoilDesigner.\18\ For the CoilDesigner model, DOE
assumed heat exchanger and fan characteristics based on physical and
catalog teardowns of unit coolers and unit cooler airflow based on
manufacturer product catalogs. DOE estimated a percentage fan power
increase using representative fan performance curves, the reported air
flow, and unit cooler system pressure drop before and after adding the
coil row, accounting for the additional ISP estimated using
CoilDesigner. Based on this analysis, DOE has tentatively determined
that increasing the number of heat exchanger rows from 2 to 3 or 3 to 4
would result in roughly a 6-percent increase in unit cooler fan power,
and increasing heat exchanger rows from 4 to 5 would result in roughly
a 4-percent unit cooler fan power increase.
---------------------------------------------------------------------------
\18\ CoilDesigner is a heat exchanger coil simulation tool.
CoilDesigner Version 4.8.20221.110 was used for this analysis.
---------------------------------------------------------------------------
Although the fan power reported in product catalogs does not appear
to change, as the number of heat exchanger rows changes, it is likely,
as indicated by the analysis described above, that the fan power is
different for these models. To evaluate the potential impact of this
variation on potential ranges of AWEF2, DOE evaluated multiple
scenarios regarding fan power increase with the Unit Cooler Performance
Database medium-temperature unit coolers. For medium-temperature unit
coolers, AWEF2 depends only on the fan power and capacity, and
questions about potential variation in the defrost energy (a factor for
low-temperature unit coolers), would not apply. The initial
construction of the Unit Cooler Performance Database, posted to the
rulemaking docket, was based on using the literature fan power as
reported (i.e., DOE did not consider any changes to fan power based on
number of rows).\19\ DOE further evaluated two alternative approaches:
(a) that the reported fan power applies for unit coolers with the least
number of tube rows and therefore, the actual fan power increases above
the levels reported in the literature with additional tube rows; and
(b) that the reported fan power applies for the unit coolers with the
greatest number of tube rows and therefore, the actual fan power
decreases below the levels reported in the literature with fewer tube
rows. For each scenario, DOE adjusted the unit cooler fan powers based
on the ISP difference determined by DOE's Coil Designer analysis. In
all cases, the calculated AWEF2 values include many that are lower than
the current baseline level. However, the number of AWEF2 values that
are lower than the current baseline level is significantly lower for
approach (b) described previously. The highest AWEF2 values are roughly
the same at 10.0 for the NOPR scenario (no fan power differences within
a family of unit coolers) and scenario (b), and are lower (close to
9.7) for scenario (a). Given that the unit coolers evaluated are all
certified as compliant with DOE standards, and the likelihood that the
reported motor power would apply for the highest-power (motor design)
operating point, DOE concludes that scenario (b) is the most likely.
DOE notes that for all three of the scenarios, the Unit Cooler
Performance Database has AWEF2 values that are higher than the max-tech
AWEF2 values calculated for the representative capacities. Thus, DOE
concludes that the max-tech efficiency levels considered in the NOPR
were not overestimated due to the potential increase in fan power as
additional tube rows are added within the range considered. Therefore,
DOE did not adjust the unit cooler AWEF2 values proposed in the
September 2023 NOPR based on the potential for additional unit cooler
rows to impose additional ISP that could require increased fan power.
The results of the three scenarios are shown in Figure 5.1 through
Figure 5.3 of the NODA support document that has been posted to the
docket.
---------------------------------------------------------------------------
\19\ The Unit Cooler Performance Database can be found at
www.regulations.gov/document/EERE-2017-BT-STD-0009-0064.
---------------------------------------------------------------------------
c. Miscellaneous Updates to the Unit Cooler Analysis
After the September 2023 NOPR was published, DOE identified an
issue in the calculation of baseline net capacities for high-
temperature unit coolers in its engineering analysis. DOE corrected
this issue for this NODA and as a result baseline AWEF2 values are
slightly less than the AWEF2 values shown in the NOPR. Additionally,
since the AWEF2 values at efficiency levels above baseline are
dependent on the baseline AWEF2 values for the high-temperature unit
cooler analysis, the AWEF2 values at higher efficiency levels are less
than those AWEF2 values shown in the NOPR. On average, the calculated
efficiencies of all high-temperature unit cooler efficiency levels have
decreased by 2-percent from the NOPR values.
In addition, DOE found an issue in the calculation of the max-tech
MPC of the UC.L.009 representative unit, which resulted in a higher
MPC. For this NODA analysis, DOE addressed this calculation issue,
which results in an MPC that is 4-percent lower than the MPC presented
in the September 2023 NOPR. When accounting for this change and the MPC
change associated with the cabinet size increase cost adder discussed
in section II.A.3.a, the MPC determined for this NODA is 2-percent less
than the MPC presented in the NOPR for this representative unit.
See section 3 of the NODA support document that has been posted to
the docket for the updated cost-efficiency curves that includes these
corrections. The analytical results (i.e., LCC, PBP, and NIA) presented
in section II.C of this document account for these corrections.
B. Trial Standard Levels
DOE analyzed the benefits and burdens of three trial standard
levels (``TSLs'') for the considered walk-in doors, panels, and
refrigeration systems in the September 2023 NOPR. 88 FR 60746, 60785-
60786.
DOE notes that the TSLs presented in this NODA are tentative and
for evaluating the analytical changes considered in the context of this
NODA and DOE may revise the number of, or structure of, these TSLs in
response to comments in future analysis. DOE further notes that the
TSLs presented in this NODA are within or close to the range of values
presented in the September 2023 NOPR.
1. Refrigeration Systems
For this NODA, DOE is presenting three TSLs to demonstrate the
changes discussed in sections II.A.2 and II.A.3 of this document that
pertain to refrigeration systems. The efficiency levels that correspond
to these TSLs for these equipment classes are shown in Table II.5
through Table II.7.
TSL 3 in this NODA includes the efficiency levels that use the
combination of design options for each representative unit at the
maximum technologically feasible (``max-tech'') level. For this NODA,
DOE notes a correction here where in the NOPR, the design option
representing max-tech for the DC.M.O.054 representative unit was mapped
to EL 7--when in fact it should have been EL 8. With the added
efficiency level in this NODA, the max-tech efficiency level for the
DC.M.O.054 representative unit is now EL 9 as shown in Table II.5. TSL
1 represents
[[Page 18566]]
the efficiency levels in this NODA that yield AWEF2 values closest to
those AWEF2 values that align with TSL 2 in the September 2023 NOPR,
which is the TSL that DOE proposed to adopt. TSL 2 in this NODA is an
intermediate TSL that is higher than TSL 1 but below the max-tech
level.
Table II.5--Refrigeration Systems Efficiency Level by Representative Unit Mapping for TSL 3
----------------------------------------------------------------------------------------------------------------
Capacity (kBtu/hr)
-----------------------------------------------------------------------
2 3 6 7 9 25 54 75 124
----------------------------------------------------------------------------------------------------------------
Dedicated Condensing Units
----------------------------------------------------------------------------------------------------------------
Low Temperature, Indoor (DC.L.I)........ ...... 2 ...... ...... 1 3 2 ...... ......
Low Temperature, Outdoor (DC.L.O)....... ...... 3 ...... ...... 5 8 5 4 ......
Medium Temperature, Indoor (DC.M.I)..... ...... ...... ...... ...... 1 3 4 3 ......
Medium Temperature, Outdoor (DC.M.O).... ...... ...... ...... ...... 8 8 9 8 9
----------------------------------------------------------------------------------------------------------------
Single-packaged Dedicated Systems
----------------------------------------------------------------------------------------------------------------
High Temperature, Ducted, Indoor 2 ...... ...... 2 ...... ...... ...... ...... ......
(SP.H.ID)..............................
High Temperature, Ducted, Outdoor 6 ...... ...... 6 ...... ...... ...... ...... ......
(SP.H.OD)..............................
High Temperature, Indoor (SP.H.I)....... 2 ...... ...... 2 ...... ...... ...... ...... ......
High Temperature, Outdoor (SP.H.O)...... 6 ...... ...... 6 ...... ...... ...... ...... ......
Low Temperature, Indoor (SP.L.I)........ 7 ...... 2 ...... ...... ...... ...... ...... ......
Low Temperature, Outdoor (SP.L.O)....... 4 ...... 4 ...... ...... ...... ...... ...... ......
Medium Temperature, Indoor (SP.M.I)..... 5 ...... ...... ...... 3 ...... ...... ...... ......
Medium Temperature, Outdoor (SP.M.O).... 9 ...... ...... ...... 5 ...... ...... ...... ......
----------------------------------------------------------------------------------------------------------------
Unit Coolers
----------------------------------------------------------------------------------------------------------------
High Temperature (UC.H)................. ...... ...... ...... ...... 1 1 ...... ...... ......
High Temperature, Ducted (UC.H.ID)...... ...... ...... ...... ...... 1 1 ...... ...... ......
Low Temperature (UC.L).................. ...... 2 ...... ...... 2 2 2 2 ......
Medium Temperature (UC.M)............... ...... 2 ...... ...... 2 2 2 2 ......
----------------------------------------------------------------------------------------------------------------
Table II.6--Refrigeration Systems Efficiency Level by Representative Unit Mapping for TSL 2
----------------------------------------------------------------------------------------------------------------
Capacity (kBtu/hr)
-----------------------------------------------------------------------
2 3 6 7 9 25 54 75 124
----------------------------------------------------------------------------------------------------------------
Dedicated Condensing Units
----------------------------------------------------------------------------------------------------------------
Low Temperature, Indoor (DC.L.I)........ ...... 1 ...... ...... 0 2 1 ...... ......
Low Temperature, Outdoor (DC.L.O)....... ...... 2 ...... ...... 4 7 4 3 ......
Medium Temperature, Indoor (DC.M.I)..... ...... ...... ...... ...... 0 2 3 2 ......
Medium Temperature, Outdoor (DC.M.O).... ...... ...... ...... ...... 3 3 4 3 4
----------------------------------------------------------------------------------------------------------------
Single-packaged Dedicated Systems
----------------------------------------------------------------------------------------------------------------
High Temperature, Ducted, Indoor 2 ...... ...... 2 ...... ...... ...... ...... ......
(SP.H.ID)..............................
High Temperature, Ducted, Outdoor 6 ...... ...... 6 ...... ...... ...... ...... ......
(SP.H.OD)..............................
High Temperature, Indoor (SP.H.I)....... 2 ...... ...... 2 ...... ...... ...... ...... ......
High Temperature, Outdoor (SP.H.O)...... 5 ...... ...... 5 ...... ...... ...... ...... ......
Low Temperature, Indoor (SP.L.I)........ 4 ...... 1 ...... ...... ...... ...... ...... ......
Low Temperature, Outdoor (SP.L.O)....... 2 ...... 2 ...... ...... ...... ...... ...... ......
Medium Temperature, Indoor (SP.M.I)..... 3 ...... ...... ...... 1 ...... ...... ...... ......
Medium Temperature, Outdoor (SP.M.O).... 8 ...... ...... ...... 3 ...... ...... ...... ......
----------------------------------------------------------------------------------------------------------------
Unit Coolers
----------------------------------------------------------------------------------------------------------------
High Temperature (UC.H)................. ...... ...... ...... ...... 0 0 ...... ...... ......
High Temperature, Ducted (UC.H.ID)...... ...... ...... ...... ...... 1 1 ...... ...... ......
Low Temperature (UC.L).................. ...... 2 ...... ...... 2 2 2 2 ......
Medium Temperature (UC.M)............... ...... 2 ...... ...... 2 2 2 2 ......
----------------------------------------------------------------------------------------------------------------
Table II.7--Refrigeration Systems Efficiency Level by Representative Unit Mapping for TSL 1
----------------------------------------------------------------------------------------------------------------
Capacity (kBtu/hr)
-----------------------------------------------------------------------
2 3 6 7 9 25 54 75 124
----------------------------------------------------------------------------------------------------------------
Dedicated Condensing Units
----------------------------------------------------------------------------------------------------------------
Low Temperature, Indoor (DC.L.I)........ ...... 1 ...... ...... 0 2 1 ...... ......
Low Temperature, Outdoor (DC.L.O)....... ...... 2 ...... ...... 4 7 4 2 ......
Medium Temperature, Indoor (DC.M.I)..... ...... ...... ...... ...... 0 2 2 2 ......
Medium Temperature, Outdoor (DC.M.O).... ...... ...... ...... ...... 2 2 2 2 2
----------------------------------------------------------------------------------------------------------------
Single-packaged Dedicated Systems
----------------------------------------------------------------------------------------------------------------
High Temperature, Ducted, Indoor 2 ...... ...... 2 ...... ...... ...... ...... ......
(SP.H.ID)..............................
High Temperature, Ducted, Outdoor 5 ...... ...... 6 ...... ...... ...... ...... ......
(SP.H.OD)..............................
High Temperature, Indoor (SP.H.I)....... 1 ...... ...... 2 ...... ...... ...... ...... ......
[[Page 18567]]
High Temperature, Outdoor (SP.H.O)...... 5 ...... ...... 5 ...... ...... ...... ...... ......
Low Temperature, Indoor (SP.L.I)........ 4 ...... 1 ...... ...... ...... ...... ...... ......
Low Temperature, Outdoor (SP.L.O)....... 0 ...... 1 ...... ...... ...... ...... ...... ......
Medium Temperature, Indoor (SP.M.I)..... 3 ...... ...... ...... 1 ...... ...... ...... ......
Medium Temperature, Outdoor (SP.M.O).... 8 ...... ...... ...... 3 ...... ...... ...... ......
----------------------------------------------------------------------------------------------------------------
Unit Coolers
----------------------------------------------------------------------------------------------------------------
High Temperature (UC.H)................. ...... ...... ...... ...... 0 0 ...... ...... ......
High Temperature, Ducted (UC.H.ID)...... ...... ...... ...... ...... 1 1 ...... ...... ......
Low Temperature (UC.L).................. ...... 2 ...... ...... 2 2 2 2 ......
Medium Temperature (UC.M)............... ...... 2 ...... ...... 2 2 2 2 ......
----------------------------------------------------------------------------------------------------------------
2. Non-Display Doors
For this NODA, DOE is presenting three TSLs to demonstrate the
changes discussed in section II.A.1 of this document that pertain to
non-display doors. The efficiency levels that correspond to these TSLs
for these equipment classes are shown table II.8.
TSL 3 in this NODA includes the efficiency levels that use the
combination of design options for each representative unit at the max-
tech level. TSL 1 and TSL 2 are intermediate TSLs between baseline and
TSL 3. The efficiency levels for each TSL are based on the updated
engineering analysis for non-display doors, as discussed in section
II.A.1 of this document and as shown in the NODA support document.
Table II.8--Non-Display Doors Efficiency Level to TSL Mapping
----------------------------------------------------------------------------------------------------------------
Trial standard level
Equipment class -----------------------------------------------
1 2 3
----------------------------------------------------------------------------------------------------------------
Non-display Doors, Manual
----------------------------------------------------------------------------------------------------------------
Low Temperature (NM.L).......................................... 1 3 5
Medium Temperature (NM.M)....................................... 1 3 6
----------------------------------------------------------------------------------------------------------------
Non-display Doors, Motorized
----------------------------------------------------------------------------------------------------------------
Low Temperature (NO.L).......................................... 1 3 5
Medium Temperature (NO.M)....................................... 1 3 6
----------------------------------------------------------------------------------------------------------------
C. Analytical Results
To quantify the impacts to consumers and the Nation from the
additional analysis of the technologies described in section II.A of
this document, DOE ran its life-cycle cost (``LCC'') and payback period
(``PBP'') analysis and national impacts analysis (``NIA'') with the
same inputs as it used in the September 2023 NOPR, with the exception
of the changes described in sections II.A and II.B of this document.
DOE also considered the potential impacts of the updated analysis
discussed in this NODA on the manufacturer impact analysis (``MIA'').
As discussed in chapter 12 of the September 2023 NOPR TSD, DOE relies
on several sources, including the engineering analysis and the
shipments analysis, to obtain inputs to quantify the potential impacts
of amended energy conservation standards on the walk-in cooler and
freezer industry. Changes to MSPs and shipments would affect industry
revenue, and, therefore, the MIA results. However, considered in
isolation, DOE does not expect that the changes to the engineering
analysis or shipments distribution detailed in this NODA would
substantively alter the industry financial results (represented by
change in industry net present value) presented in the September 2023
NOPR. DOE will assess and incorporate the most up-to-date data in any
subsequent MIA conducted for this rulemaking.
1. Life-Cycle Cost and Payback Period Analysis
DOE analyzed the economic impacts on walk-in coolers and freezers
consumers by looking at the effects that potential amended standards at
each TSL would have on the LCC and PBP. The detailed description of how
DOE calculates its LCC impacts can be found in chapter 8 and associated
appendices of the September 2023 NOPR TSD.
In general, higher-efficiency equipment affect consumers in two
ways: (1) purchase price increases and (2) annual operating costs
decrease. Inputs used for calculating the LCC and PBP include total
installed costs (i.e., product price plus installation costs), and
operating costs (i.e., annual energy use, energy prices, energy price
trends, repair costs, and maintenance costs). The LCC calculation also
uses product lifetime and a discount rate. For this NODA, DOE
maintained the same methods and modeling assumptions discussed in
chapter 8 of the September 2023 NOPR TSD with the exception of the
revised engineering analysis discussed in section II.A of this document
and TSL composition discussed in section II.B of this document.
a. Application of the Low-GWP Refrigerant Transition to Specific
Regions
As discussed in section II.A.2.c of this document, the states of
California and Washington require the use of sub-150-GWP refrigerants.
In the September 2023 NOPR, DOE conducted its LCC analysis at the
geographic level of Census regions, where the region containing the
states of California and Washington is the Western Region
[[Page 18568]]
(Region 4).\20\ To approximate any additional costs associated with
moving to low-GWP refrigerants to consumers in California and
Washington DOE applied the cost of the additional design options
determined in section II.A.2.c of this document to the fraction of
consumers in Western Census Region based on population.\21\ Theses
weights and design option cost are shown in table II.9.
---------------------------------------------------------------------------
\20\ See: https://www2.census.gov/geo/pdfs/maps-data/maps/reference/us_regdiv.pdf.
\21\ See: https://www.census.gov/data/tables/time-series/demo/popest/2020s-state-total.html.
Table II.9--Low-GWP Refrigerant Cost Adders
----------------------------------------------------------------------------------------------------------------
Capacity Cost adder
EC (kBtu/hr) Census region ($) Weight
----------------------------------------------------------------------------------------------------------------
DC.M.I.......................................... 3 4 0 0.59
3 4 0 0.41
9 4 0 0.59
9 4 0 0.41
25 4 381.20 0.59
25 4 0 0.41
54 4 0 0.59
54 4 0 0.41
75 4 0 0.59
75 4 0 0.41
DC.M.O.......................................... 3 4 0 0.59
3 4 0 0.41
9 4 0 0.59
9 4 0 0.41
25 4 95.94 0.59
25 4 0 0.41
54 4 0 0.59
54 4 0 0.41
75 4 0 0.59
75 4 0 0.41
124 4 0 0.59
124 4 0 0.41
----------------------------------------------------------------------------------------------------------------
DOE seeks comment on its approach to applying the transition to
low-GWP refrigerant to specific regions.
b. Results for Refrigeration Systems
Table II.10 through table II.14 show the LCC and PBP results for
the TSLs for each category of refrigeration system equipment impacted
in this NODA. In the first of each pair of tables by equipment category
(dedicated refrigeration systems, single-packaged dedicated
refrigeration systems, etc.), the simple payback is measured relative
to the baseline equipment. In the second table, impacts are measured
relative to the efficiency distribution in the no-new-standards case in
the compliance year. The savings refer only to consumers who are
affected by a standard at a given TSL. Those who already purchase
equipment with efficiency at or above a given TSL are not affected.
Consumers for whom the LCC increases at a given TSL experience a net
cost.
Table II.10--Average LCC and PBP Results for Dedicated Condensing Units
--------------------------------------------------------------------------------------------------------------------------------------------------------
Average costs (2023$)
------------------------------------------------------------------------------ Simple payback Average
TSL First year's Lifetime period (yrs) lifetime (yrs)
Installed cost operation cost operating cost LCC
--------------------------------------------------------------------------------------------------------------------------------------------------------
Dedicated Condensing Units, Low Temperature, Indoor (DC.L.I)
--------------------------------------------------------------------------------------------------------------------------------------------------------
0......................................... 7,643....................... 2,486 22,151 29,793 0.0 10.6
1......................................... 7,771....................... 2,435 21,844 29,615 3.2 10.6
2......................................... 7,771....................... 2,435 21,844 29,615 3.2 10.6
3......................................... 10,891...................... 2,331 22,956 33,847 inf 10.6
--------------------------------------------------------------------------------------------------------------------------------------------------------
Dedicated Condensing Units, Low Temperature, Outdoor (DC.L.O)
--------------------------------------------------------------------------------------------------------------------------------------------------------
0......................................... 26,579...................... 3,790 39,853 66,432 0.0 10.5
1......................................... 26,799...................... 3,731 39,540 66,339 5.3 10.5
2......................................... 26,885...................... 3,724 39,546 66,430 7.5 10.5
3......................................... 38,360...................... 3,321 43,510 81,870 inf 10.5
--------------------------------------------------------------------------------------------------------------------------------------------------------
Dedicated Condensing Units, Medium Temperature, Indoor (DC.M.I)
--------------------------------------------------------------------------------------------------------------------------------------------------------
0......................................... 3,783....................... 1,164 10,379 14,162 0.0 10.5
1......................................... 3,882....................... 1,123 10,126 14,008 3.0 10.5
2......................................... 3,921....................... 1,111 10,058 13,979 3.3 10.5
[[Page 18569]]
3......................................... 5,107....................... 1,037 10,214 15,320 64.4 10.5
--------------------------------------------------------------------------------------------------------------------------------------------------------
Dedicated Condensing Units, Medium Temperature, Outdoor (DC.M.O)
--------------------------------------------------------------------------------------------------------------------------------------------------------
0......................................... 5,757....................... 1,661 15,136 20,892 0.0 10.6
1......................................... 5,761....................... 1,648 15,041 20,802 0.4 10.6
2......................................... 5,884....................... 1,607 14,799 20,683 2.9 10.6
3......................................... 8,470....................... 1,297 14,004 22,474 18.7 10.6
--------------------------------------------------------------------------------------------------------------------------------------------------------
Note: The results for each TSL are calculated assuming that all consumers use equipment at that efficiency level. The PBP is measured relative to the
baseline equipment.
Table II.11--LCC Savings Relative to the Base Case Efficiency
Distribution for Dedicated Condensing Units
------------------------------------------------------------------------
Average savings--
TSL % Consumers with impacted consumers
net cost (2023$)
------------------------------------------------------------------------
Dedicated Condensing Units, Low Temperature, Indoor (DC.L.I)
------------------------------------------------------------------------
1............................... 7 276
2............................... 7 276
3............................... 100 -4,054
------------------------------------------------------------------------
Dedicated Condensing Units, Low Temperature, Outdoor (DC.L.O)
------------------------------------------------------------------------
1............................... 28 93
2............................... 47 2
3............................... 100 -15,438
------------------------------------------------------------------------
Dedicated Condensing Units, Medium Temperature, Indoor (DC.M.I)
------------------------------------------------------------------------
1............................... 1 594
2............................... 2 709
3............................... 97 -1,159
------------------------------------------------------------------------
Dedicated Condensing Units, Medium Temperature, Outdoor (DC.M.O)
------------------------------------------------------------------------
1............................... 0 90
2............................... 3 209
3............................... 95 -1,582
------------------------------------------------------------------------
Note: The savings represent the average LCC for affected consumers.
Table II.12--Average LCC and PBP Results for Single-Packaged Dedicated Systems
--------------------------------------------------------------------------------------------------------------------------------------------------------
Average costs (2023$)
---------------------------------------------------------------- Simple Average
TSL First year's Lifetime payback lifetime
Installed operation operating LCC period (yrs) (yrs)
cost cost cost
--------------------------------------------------------------------------------------------------------------------------------------------------------
Single-packaged Dedicated Systems, High Temperature, Ducted, Indoor (SP.H.ID)
--------------------------------------------------------------------------------------------------------------------------------------------------------
0....................................................... 2,051 436 3,977 6,027 0.0 10.5
1....................................................... 2,145 370 3,586 5,731 1.7 10.5
2....................................................... 2,145 370 3,586 5,731 1.7 10.5
3....................................................... 2,145 370 3,586 5,731 1.7 10.5
--------------------------------------------------------------------------------------------------------------------------------------------------------
Single-packaged Dedicated Systems, High Temperature, Ducted, Outdoor (SP.H.OD)
--------------------------------------------------------------------------------------------------------------------------------------------------------
0....................................................... 2,820 590 5,401 8,221 0.0 10.5
1....................................................... 3,119 476 4,811 7,930 3.5 10.5
2....................................................... 3,146 474 4,819 7,965 3.8 10.5
3....................................................... 3,146 474 4,819 7,965 3.8 10.5
--------------------------------------------------------------------------------------------------------------------------------------------------------
Single-packaged Dedicated Systems, High Temperature, Indoor (SP.H.I)
--------------------------------------------------------------------------------------------------------------------------------------------------------
0....................................................... 1,978 255 2,709 4,688 0.0 10.5
1....................................................... 2,006 230 2,557 4,563 1.3 10.5
2....................................................... 2,035 226 2,550 4,585 2.5 10.5
[[Page 18570]]
3....................................................... 2,035 226 2,550 4,585 2.5 10.5
--------------------------------------------------------------------------------------------------------------------------------------------------------
Single-packaged Dedicated Systems, High Temperature, Outdoor (SP.H.O)
--------------------------------------------------------------------------------------------------------------------------------------------------------
0....................................................... 2,857 357 3,829 6,686 0.0 10.5
1....................................................... 2,948 319 3,629 6,577 3.1 10.5
2....................................................... 2,948 319 3,629 6,577 3.1 10.5
3....................................................... 1,764 62 2,033 3,797 inf 10.5
--------------------------------------------------------------------------------------------------------------------------------------------------------
Single-packaged Dedicated Systems, Low Temperature, Indoor (SP.L.I)
--------------------------------------------------------------------------------------------------------------------------------------------------------
0....................................................... 3,755 732 6,963 10,718 0.0 10.5
1....................................................... 3,947 665 6,621 10,568 3.9 10.5
2....................................................... 3,947 665 6,621 10,568 3.9 10.5
3....................................................... 3,947 665 6,621 10,568 3.9 10.5
--------------------------------------------------------------------------------------------------------------------------------------------------------
Single-packaged Dedicated Systems, Low Temperature, Outdoor (SP.L.O)
--------------------------------------------------------------------------------------------------------------------------------------------------------
0....................................................... 4,951 967 9,202 14,153 0.0 10.6
1....................................................... 4,952 955 9,121 14,074 0.2 10.6
2....................................................... 4,974 951 9,095 14,068 1.5 10.6
3....................................................... 6,129 920 9,641 15,771 inf 10.6
--------------------------------------------------------------------------------------------------------------------------------------------------------
Single-packaged Dedicated Systems, Medium Temperature, Indoor (SP.M.I)
--------------------------------------------------------------------------------------------------------------------------------------------------------
0....................................................... 4,002 713 6,958 10,959 0.0 10.5
1....................................................... 4,177 674 6,800 10,977 7.8 10.5
2....................................................... 4,177 674 6,800 10,977 7.8 10.5
3....................................................... 5,042 666 7,307 12,349 inf 10.5
--------------------------------------------------------------------------------------------------------------------------------------------------------
Single-packaged Dedicated Systems, Medium Temperature, Outdoor (SP.M.O)
--------------------------------------------------------------------------------------------------------------------------------------------------------
0....................................................... 4,795 667 7,023 11,818 0.0 10.5
1....................................................... 4,857 636 6,846 11,703 2.5 10.5
2....................................................... 4,857 636 6,846 11,703 2.5 10.5
3....................................................... 5,806 632 7,436 13,242 inf 10.5
--------------------------------------------------------------------------------------------------------------------------------------------------------
Note: The results for each TSL are calculated assuming that all consumers use equipment at that efficiency level. The PBP is measured relative to the
baseline equipment.
Table II.13--LCC Savings Relative to the Base Case Efficiency
Distribution for Single-Packaged Dedicated Systems
------------------------------------------------------------------------
Average savings--
TSL % Consumers with impacted
net cost consumers (2023$)
------------------------------------------------------------------------
Single-packaged Dedicated Systems, High Temperature, Ducted, Indoor
(SP.H.ID)
------------------------------------------------------------------------
1............................... 0 296
2............................... 0 296
3............................... 0 296
------------------------------------------------------------------------
Single-packaged Dedicated Systems, High Temperature, Ducted, Outdoor
(SP.H.OD)
------------------------------------------------------------------------
1............................... 5 291
2............................... 16 256
3............................... 16 256
------------------------------------------------------------------------
Single-packaged Dedicated Systems, High Temperature, Indoor (SP.H.I)
------------------------------------------------------------------------
1............................... 2 124
2............................... 3 103
3............................... 3 103
------------------------------------------------------------------------
Single-packaged Dedicated Systems, High Temperature, Outdoor (SP.H.O)
------------------------------------------------------------------------
1............................... 3 108
2............................... 3 108
3............................... 21 -55
------------------------------------------------------------------------
Single-packaged Dedicated Systems, Low Temperature, Indoor (SP.L.I)
------------------------------------------------------------------------
1............................... 8 150
[[Page 18571]]
2............................... 8 150
3............................... 8 150
------------------------------------------------------------------------
Single-packaged Dedicated Systems, Low Temperature, Outdoor (SP.L.O)
------------------------------------------------------------------------
1............................... 0 105
2............................... 20 85
3............................... 100 -1,618
------------------------------------------------------------------------
Single-packaged Dedicated Systems, Medium Temperature, Indoor (SP.M.I)
------------------------------------------------------------------------
1............................... 27 -17
2............................... 27 -17
3............................... 100 -1,390
------------------------------------------------------------------------
Single-packaged Dedicated Systems, Medium Temperature, Outdoor (SP.M.O)
------------------------------------------------------------------------
1............................... 6 114
2............................... 6 114
3............................... 100 -1,425
------------------------------------------------------------------------
Note: The savings represent the average LCC for affected consumers.
Table II.14--Average LCC and PBP Results for Unit Coolers
--------------------------------------------------------------------------------------------------------------------------------------------------------
Average costs (2023$)
---------------------------------------------------------------- Simple Average
TSL First year's Lifetime payback lifetime
Installed cost operation operating LCC period (yrs) (yrs)
cost cost
--------------------------------------------------------------------------------------------------------------------------------------------------------
Unit Coolers, High Temperature (UC.H)
--------------------------------------------------------------------------------------------------------------------------------------------------------
0....................................................... 3,083 479 4,595 7,678 0.0 10.5
1....................................................... 3,083 479 4,595 7,678 0.0 10.5
2....................................................... 3,083 479 4,595 7,678 0.0 10.5
3....................................................... 3,223 474 4,642 7,865 inf 10.5
--------------------------------------------------------------------------------------------------------------------------------------------------------
Unit Coolers, High Temperature, Ducted (UC.H.ID)
--------------------------------------------------------------------------------------------------------------------------------------------------------
0....................................................... 3,161 681 6,111 9,271 0.0 10.5
1....................................................... 3,212 642 5,859 9,071 1.5 10.5
2....................................................... 3,212 642 5,859 9,071 1.5 10.5
3....................................................... 3,212 642 5,859 9,071 1.5 10.5
--------------------------------------------------------------------------------------------------------------------------------------------------------
Unit Coolers, Low Temperature (UC.L)
--------------------------------------------------------------------------------------------------------------------------------------------------------
0....................................................... 2,658 4,413 34,322 36,980 0.0 10.5
1....................................................... 2,918 4,186 32,772 35,690 1.3 10.5
2....................................................... 2,918 4,186 32,772 35,690 1.3 10.5
3....................................................... 2,918 4,186 32,772 35,690 1.3 10.5
--------------------------------------------------------------------------------------------------------------------------------------------------------
Unit Coolers, Medium Temperature (UC.M)
--------------------------------------------------------------------------------------------------------------------------------------------------------
0....................................................... 2,468 1,675 13,649 16,118 0.0 10.6
1....................................................... 2,569 1,631 13,373 15,942 2.7 10.6
2....................................................... 2,569 1,631 13,373 15,942 2.7 10.6
3....................................................... 2,569 1,631 13,373 15,942 2.7 10.6
--------------------------------------------------------------------------------------------------------------------------------------------------------
Note: The results for each TSL are calculated assuming that all consumers use equipment at that efficiency level. The PBP is measured relative to the
baseline equipment.
Table II.15--LCC Savings Relative to the Base Case Efficiency
Distribution for Unit Coolers
------------------------------------------------------------------------
Average savings--
TSL % Consumers with impacted consumers
net cost (2023$)
------------------------------------------------------------------------
Unit Coolers, High Temperature (UC.H)
------------------------------------------------------------------------
1............................... n/a n/a
2............................... n/a n/a
[[Page 18572]]
3............................... 100 -187
------------------------------------------------------------------------
Unit Coolers, High Temperature, Ducted (UC.H.ID)
------------------------------------------------------------------------
1............................... 0 201
2............................... 0 201
3............................... 0 201
------------------------------------------------------------------------
Unit Coolers, Low Temperature (UC.L)
------------------------------------------------------------------------
1............................... 10 1,290
2............................... 10 1,290
3............................... 10 1,290
------------------------------------------------------------------------
Unit Coolers, Medium Temperature (UC.M)
------------------------------------------------------------------------
1............................... 23 176
2............................... 23 176
3............................... 23 176
------------------------------------------------------------------------
Note: The savings represent the average LCC for affected consumers.
c. Results for Non-Display Doors
Table II.16 through table II.19 show the LCC and PBP results for
the TSLs for each non-display doors equipment class impacted in this
NODA. In the first of each pair of tables by equipment class (manual
non-display doors, motorized non-display doors), the simple payback is
measured relative to the baseline equipment. In the second table,
impacts are measured relative to the efficiency distribution in the no-
new-standards case in the compliance year. The savings refer only to
consumers who are affected by a standard at a given TSL. Those who
already purchase equipment with efficiency at or above a given TSL are
not affected. Consumers for whom the LCC increases at a given TSL
experience a net cost.
As discussed in the September 2023 NOPR, to estimate the impacts of
improved efficiency on walk-in envelope components (e.g., panels,
doors), DOE must first establish the efficiencies and energy use of the
connected refrigeration equipment. 88 FR 60746, 60786. For the purposes
of this NODA, DOE has presented the results for non-display doors based
on both the baseline and max-tech refrigeration system to show the
range of potential impacts associated with each analyzed TSL.
Table II.16--Average LCC and PBP Results for Manual Non-Display Doors
--------------------------------------------------------------------------------------------------------------------------------------------------------
Average costs (2023$)
---------------------------------------------------------------- Simple payback Average
TSL First year's Lifetime period (yrs) lifetime (yrs)
Installed cost operation cost operating cost LCC
--------------------------------------------------------------------------------------------------------------------------------------------------------
Non-display Doors, Manual, Low Temperature (NM.L)
Connected to a Baseline Refrigeration System
--------------------------------------------------------------------------------------------------------------------------------------------------------
0....................................................... 2,663 315 2,079 4,742 0.0 8.7
1....................................................... 2,754 237 1,566 4,319 1.2 8.7
2....................................................... 2,854 161 1,068 3,922 1.3 8.7
3....................................................... 3,136 147 975 4,111 2.8 8.7
--------------------------------------------------------------------------------------------------------------------------------------------------------
Connected to a Max Tech Refrigeration System
--------------------------------------------------------------------------------------------------------------------------------------------------------
0....................................................... 2,574 347 2,289 4,863 0.0 8.7
1....................................................... 2,705 240 1,582 4,288 1.2 8.7
2....................................................... 2,833 159 1,050 3,883 1.4 8.7
3....................................................... 3,136 145 961 4,097 2.8 8.7
--------------------------------------------------------------------------------------------------------------------------------------------------------
Non-display Doors, Manual, Medium Temperature (NM.M)
Connected to a Baseline Refrigeration System
--------------------------------------------------------------------------------------------------------------------------------------------------------
0....................................................... 2,766 77 505 3,271 0.0 8.8
1....................................................... 2,827 51 337 3,163 2.4 8.8
2....................................................... 2,900 35 233 3,132 3.2 8.8
3....................................................... 3,229 32 211 3,439 10.4 8.8
--------------------------------------------------------------------------------------------------------------------------------------------------------
[[Page 18573]]
Connected to a Max Tech Refrigeration System
--------------------------------------------------------------------------------------------------------------------------------------------------------
0....................................................... 2,605 108 714 3,319 0.0 8.8
1....................................................... 2,736 56 368 3,105 2.5 8.8
2....................................................... 2,850 37 246 3,095 3.4 8.8
3....................................................... 3,229 34 226 3,454 8.4 8.8
--------------------------------------------------------------------------------------------------------------------------------------------------------
Note: The results for each TSL are calculated assuming that all consumers use equipment at that efficiency level. The PBP is measured relative to the
baseline equipment.
Table II.17--LCC Savings Relative to the Base Case Efficiency
Distribution for Manual Non-Display Doors
------------------------------------------------------------------------
Average savings--
TSL % Consumers with impacted consumers
net cost (2023$)
------------------------------------------------------------------------
Non-display Doors, Manual, Low Temperature (NM.L)
Connected to a Baseline Refrigeration System
------------------------------------------------------------------------
1............................... 1 607
2............................... 1 1,049
3............................... 5 847
------------------------------------------------------------------------
Connected to a Max Tech Refrigeration System
------------------------------------------------------------------------
1............................... 1 575
2............................... 1 980
3............................... 5 766
------------------------------------------------------------------------
Non-display Doors, Manual, Medium Temperature (NM.M)
Connected to a Baseline Refrigeration System
------------------------------------------------------------------------
1............................... 3 233
2............................... 8 263
3............................... 69 -91
------------------------------------------------------------------------
Connected to a Max Tech Refrigeration System
------------------------------------------------------------------------
1............................... 4 214
2............................... 9 224
3............................... 78 -135
------------------------------------------------------------------------
Note: The savings represent the average LCC for affected consumers.
Table II.18--Average LCC and PBP Results for Motorized Non-Display Doors
--------------------------------------------------------------------------------------------------------------------------------------------------------
Average costs (2023$)
---------------------------------------------------------------- Simple payback Average
TSL First year's Lifetime period (yrs) lifetime (yrs)
Installed cost operation cost operating cost LCC
--------------------------------------------------------------------------------------------------------------------------------------------------------
Non-display Doors, Motorized, Low Temperature (NO.L)
Connected to a Baseline Refrigeration System
--------------------------------------------------------------------------------------------------------------------------------------------------------
0....................................................... 7,120 495 3,244 10,364 0.0 8.7
1....................................................... 7,240 362 2,376 9,615 0.9 8.7
2....................................................... 7,367 253 1,663 9,029 1.0 8.7
3....................................................... 7,688 223 1,466 9,154 2.1 8.7
--------------------------------------------------------------------------------------------------------------------------------------------------------
Connected to a Max Tech Refrigeration System
--------------------------------------------------------------------------------------------------------------------------------------------------------
0....................................................... 7,102 480 3,146 10,248 0.0 8.7
1....................................................... 7,233 341 2,237 9,470 0.9 8.7
2....................................................... 7,363 237 1,558 8,921 1.1 8.7
3....................................................... 7,688 210 1,381 9,069 2.2 8.7
--------------------------------------------------------------------------------------------------------------------------------------------------------
[[Page 18574]]
Non-display Doors, Motorized, Medium Temperature (NO.M)
Connected to a Baseline Refrigeration System
--------------------------------------------------------------------------------------------------------------------------------------------------------
0....................................................... 7,333 91 597 7,930 0.0 8.8
1....................................................... 7,377 66 436 7,813 1.8 8.8
2....................................................... 7,435 50 331 7,767 2.5 8.8
3....................................................... 7,704 45 298 8,002 8.1 8.8
--------------------------------------------------------------------------------------------------------------------------------------------------------
Connected to a Max Tech Refrigeration System
--------------------------------------------------------------------------------------------------------------------------------------------------------
0....................................................... 7,059 151 992 8,051 0.0 8.8
1....................................................... 7,190 81 536 7,727 1.9 8.8
2....................................................... 7,307 56 373 7,679 2.6 8.8
3....................................................... 7,704 50 333 8,037 6.4 8.8
--------------------------------------------------------------------------------------------------------------------------------------------------------
Note: The results for each TSL are calculated assuming that all consumers use equipment at that efficiency level. The PBP is measured relative to the
baseline equipment.
Table II.19--LCC Savings Relative to the Base Case Efficiency
Distribution for Manual Non-Display Doors
------------------------------------------------------------------------
Average savings--
TSL % Consumers with impacted consumers
net cost (2023$)
------------------------------------------------------------------------
Non-display Doors, Motorized, Low Temperature (NO.L)
Connected to a Baseline Refrigeration System
------------------------------------------------------------------------
1............................... 0 819
2............................... 0 1,417
3............................... 2 1,291
------------------------------------------------------------------------
Connected to a Max Tech Refrigeration System
------------------------------------------------------------------------
1............................... 0 778
2............................... 0 1,326
3............................... 2 1,179
------------------------------------------------------------------------
Non-display Doors, Motorized, Medium Temperature (NO.M)
Connected to a Baseline Refrigeration System
------------------------------------------------------------------------
1............................... 1 349
2............................... 3 424
3............................... 42 77
------------------------------------------------------------------------
Connected to a Max Tech Refrigeration System
------------------------------------------------------------------------
1............................... 1 324
2............................... 4 372
3............................... 51 14
------------------------------------------------------------------------
Note: The savings represent the average LCC for affected consumers.
2. National Impacts Analysis
This section presents DOE's estimates of the changes in national
energy savings (``NES'') and the net present value (``NPV'') of
consumer benefits that would result from each of the TSLs as potential
amended standards for the equipment under consideration in this NODA.
For this NODA, DOE maintained the methodologies and modeling
assumptions that were used in the 2023 September NOPR. For brevity the
NIA results are presented here by equipment category (i.e.,
refrigeration systems), the results for each equipment class can be
found in section 6 of the NODA support document.
The detailed description of how DOE calculates its national impacts
can be found in chapter 10 and associated appendices of the September
2023 NOPR TSD.
a. Non-Display Doors
As discussed in the September 2023 NOPR, the energy savings from
improved insulation or reduced heat infiltration would be realized as
reduced load on the attached refrigeration systems; however, for the
purpose of reporting, these energy savings are attributed to the
individual door in question. 88 FR 60746, 60788. For this NODA, when
determining the NES and NPV of consumer benefits of
[[Page 18575]]
each TSL DOE bounds the range of potential costs and benefits for non-
display doors when they are connected to max-tech refrigeration systems
(the low bound), and baseline refrigeration systems (the high bound).
These results are shown in table II.21 and table II.23.
b. Significance of Energy Savings
To estimate the energy savings attributable to potential amended
standards for walk-in refrigeration systems, DOE compared their energy
consumption under the no-new-standards case to their anticipated energy
consumption under each TSL. The savings are measured over the entire
lifetime of equipment purchased in the 30-year period that begins in
the year of anticipated compliance with amended standards (2027-2056).
Table II.20 and table II.21 present DOE's projections of the NES for
each TSL considered for walk-in refrigeration systems shown in section
II.B. The savings were calculated using the approach described in
chapter 10 of the September 2023 NOPR TSD.\22\
---------------------------------------------------------------------------
\22\ See: www.regulations.gov/document/EERE-2017-BT-STD-0009-
0046.
Table II.20--Cumulative Full-Fuel Cycle National Energy Savings for Walk-In Coolers and Freezer Refrigeration
Systems (Quads); 30 Years of Shipments
[2027-2056]
----------------------------------------------------------------------------------------------------------------
Trial standard level
-----------------------------------------------
1 2 3
----------------------------------------------------------------------------------------------------------------
(quads)
----------------------------------------------------------------------------------------------------------------
Primary energy.................................................. 0.86 1.11 3.51
FFC energy...................................................... 0.89 1.14 3.61
----------------------------------------------------------------------------------------------------------------
Table II.21--Cumulative Full-Fuel Cycle National Energy Savings for Walk-In Coolers and Freezers: Non-Display
Doors (Quads); 30 Years of Shipments
[2027-2056]
----------------------------------------------------------------------------------------------------------------
Trial standard level
-----------------------------------------------
1 2 3
----------------------------------------------------------------------------------------------------------------
(quads)
----------------------------------------------------------------------------------------------------------------
Primary energy.................................................. 0.27 to 0.28 0.58 to 0.61 0.65 to 0.70
FFC energy...................................................... 0.28 to 0.29 0.59 to 0.63 0.67 to 0.72
----------------------------------------------------------------------------------------------------------------
c. Net Present Value of Consumer Costs and Benefits
DOE estimated the cumulative NPV of the total costs and savings for
consumers that would result from the TSLs considered for walk-in
refrigeration systems. In accordance with the Office of Management and
Budget's guidelines on regulatory analysis,\23\ DOE calculated NPV
using both a 7-percent and a 3-percent real discount rate. Table II.22
and table II.23 show the consumer NPV results with impacts counted over
the lifetime of walk-in coolers and freezers refrigeration systems and
non-display doors purchased in 2027-2056.
---------------------------------------------------------------------------
\23\ U.S. Office of Management and Budget. Circular A-4:
Regulatory Analysis. September 17, 2003. www.whitehouse.gov/wp-content/uploads/legacy_drupal_files/omb/circulars/A4/a-4.pdf (last
accessed April 26, 2023).
Table II.22--Cumulative Net Present Value of Consumer Benefits for Walk-In Coolers and Freezers Refrigeration
Systems; 30 Years of Shipments
[2027-2056]
----------------------------------------------------------------------------------------------------------------
Trial standard level
Discount rate -------------------------------------------------
1 2 3
----------------------------------------------------------------------------------------------------------------
(billion 2023$)
----------------------------------------------------------------------------------------------------------------
3 percent..................................................... 1.53 1.57 -25.45
7 percent..................................................... 0.64 0.62 -13.15
----------------------------------------------------------------------------------------------------------------
[[Page 18576]]
Table II.23--Cumulative Net Present Value of Consumer Benefits for Walk-In Coolers and Freezers: Non-Display
Doors; 30 Years of Shipments
[2027-2056]
----------------------------------------------------------------------------------------------------------------
Trial standard level
Discount rate -------------------------------------------------
1 2 3
----------------------------------------------------------------------------------------------------------------
(billion 2022$)
----------------------------------------------------------------------------------------------------------------
3 percent..................................................... 0.78 to 0.83 1.57 to 1.72 -0.43 to -0.24
7 percent..................................................... 0.35 to 0.37 0.69 to 0.76 -0.43 to -0.35
----------------------------------------------------------------------------------------------------------------
D. Updated Equations for Proposed Standards
1. Energy Consumption Equations for Non-Display Doors
In the September 2023 NOPR, DOE proposed amended energy
conservation standards for walk-in non-display doors at TSL 2 from the
NOPR analysis. 88 FR 60746, 60748. Table II.24 presents updated MDEC
curves for the affected equipment classes at the same trial standard
level proposed in the September 2023 NOPR using the updated analysis
presented in this NODA.
Table II.24--Changes to Energy Conservation Standards for Walk-In Non-
Display Doors Proposed in the September 2023 NOPR
------------------------------------------------------------------------
TSL 2 NOPR
Equipment class equations for TSL 2 NODA equations
MDEC (kWh/day) * for MDEC (kWh/day) *
------------------------------------------------------------------------
Non-Display Door, Manual, 0.01 x And + 0.25 0.01 x And + 0.25 +
Medium Temperature. 0.33a + 0.25b +
0.07c + 0.24d.
Non-Display Door, Manual, Low 0.06 x And + 1.32 0.06 x And + 1.35 +
Temperature. 0.40a + 1.42b +
0.09c + 0.30d +
0.85e.
Non-Display Door, Motorized, 0.01 x And + 0.39 0.01 x And + 0.39 +
Medium Temperature. 0.33a + 0.25b +
0.07c + 0.24d.
Non-Display Door, Motorized, 0.05 x And + 1.56 0.05 x And + 1.59 +
Low Temperature. 0.40a + 1.42b +
0.09c + 0.30d +
0.85e.
------------------------------------------------------------------------
And represents the surface area of the non-display door.
a = 1 for a door with lighting and = 0 for a door without lighting.
b = 1 for a door with a heated viewport window and = 0 for a door
without a heated viewport window.
c = 1 for a door with a digital temperature display without alarms and =
0 for a door without a digital display without alarms.
d = 1 for a door with a digital temperature display with alarms and = 0
for a door without a digital temperature display with alarms.
e = 1 for a door with a heated pressure relief vent and = 0 for a door
without a heated pressure relief vent.
2. AWEF2 Equations
In the September 2023 NOPR, DOE proposed amended energy
conservation standards for walk-in refrigeration system equipment at
TSL 2 from the NOPR analysis. 88 FR 60746, 60748. The equations for the
proposed amended energy conservation standards for dedicated condensing
units and single-packaged dedicated systems generally followed the
trends of the TSL 2 levels determined for the analyzed representative
capacities. For unit coolers, DOE proposed energy conservation
standards that do not vary with capacity.
AHRI and Hussmann commented on the proposed energy conservation
standards for unit coolers by providing plots for medium- and low-
temperature unit coolers showing that DOE proposed AWEF2 standards
equations that resulted in AWEF2 values above the AWEF2 values
determined for EL 2 (i.e., the max-tech efficiency level) for certain
representative capacities. (AHRI, No. 72 at pp. 4-5; Hussmann, No. 75
at pp. 2-3)
DOE notes that it proposed unit cooler standards that do not depend
on capacity, averaging the proposed TSL 2 efficiency levels of the
representative capacities within each unit cooler class. Thus, the
proposed standard levels at higher representative capacities were above
the max-tech efficiency levels determined for those capacities. DOE
analyzed the unit cooler performance database to determine if the
proposed standards for medium- and low-temperature were technologically
feasible. DOE was able to identify low-temperature unit cooler models
above the standard level proposed in the September 2023 NOPR across the
full range of capacities analyzed. Therefore, DOE has tentatively
concluded that the AWEF2 standard proposed in the September 2023 NOPR
for low-temperature unit coolers is technologically feasible. DOE was
unable to identify medium-temperature unit cooler models at efficiency
levels at or above the standard level proposed in the September 2023
NOPR at certain capacities. Therefore, DOE has revised the medium-
temperature unit cooler standard equation proposed in the September
2023 NOPR such that it never exceeds the maximum technology level
identified in the unit cooler performance database for given capacity
ranges. Revised medium-temperature unit cooler standard equations are
presented in section 7 of the NODA support document.
In the September 2023 NOPR, DOE proposed an AWEF2 standard level
for medium-temperature outdoor single-packaged dedicated systems of
7.11 for models with capacities greater than or equal to 9 kBtu/h. 88
FR 60746, 60853. In response to the September 2023 NOPR, the Efficiency
Advocates commented that DOE's proposed AWEF2 standard of 7.11
corresponds to EL 1 for 9 kBtu/h medium-temperature outdoor single-
packaged dedicated systems even though table IV.26 in the September
2023 NOPR maps TSL 2 to EL 3 (Efficiency Advocates, No. 77 at p. 6).
DOE acknowledges that table IV.26
[[Page 18577]]
in the September 2023 NOPR maps TSL 2 for 9 kBtu/h medium-temperature
single-packaged outdoor dedicated systems to EL 3, which has an AWEF2
of 7.5. 88 FR 60746, 60787. Additionally, table 5A.5.21 in appendix 5A
in the September 2023 NOPR TSD specifies that EL 3 of the 9 kBtu/h
medium-temperature outdoor single-packaged dedicated systems
(SP.M.O.009) corresponds to an AWEF2 of 7.5. However, the proposed
standard level for medium-temperature outdoor single-packaged dedicated
systems was erroneously set based on an AWEF2 of 7.11 for the
representative capacity of 9 kBtu/h. DOE has corrected this in table
7.1 of the NODA Support Document.
Section 7 of the NODA Support Document presents updated AWEF2
calculations for refrigeration system equipment classes at the trial
standards levels presented in this NODA.
III. Public Participation
DOE requests comment on the updated efficiency levels, incremental
MPCs, LCC, PBP, and NIA results for walk-in refrigeration systems
presented in the NODA. As noted in the September 2023 NOPR, DOE may
adopt energy efficiency levels that are either higher or lower than the
proposed standards, or some combination of level(s) that incorporate
the proposed standards in part.
DOE will accept comments, data, and information regarding this NODA
no later than the date provided in the DATES section at the beginning
of this document. 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 www.regulations.gov. The
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 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 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 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 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 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.
No telefacsimiles (``faxes'') will be accepted.
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 and, if possible, they should carry the
electronic signature of the author.
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 two well-marked 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. DOE will make
its own determination about the confidential status of the information
and treat it according to its determination.
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).
IV. Approval of the Office of the Secretary
The Secretary of Energy has approved publication of this
notification of data availability and request for comment.
Signing Authority
This document of the Department of Energy was signed on March 11,
2024, by Jeffrey Marootian, Principal Deputy Assistant Secretary for
Energy Efficiency and Renewable Energy, pursuant to delegated authority
from the Secretary of Energy. That document with the original signature
and date is maintained by DOE. For administrative purposes only, and in
compliance with requirements of the Office of the Federal Register, the
undersigned DOE Federal Register Liaison Officer has been authorized to
sign and submit the document in electronic format for publication, as
an official document of the Department of Energy. This administrative
process in no way alters the legal effect of this document upon
publication in the Federal Register.
[[Page 18578]]
Signed in Washington, DC, on March 11, 2024.
Treena V. Garrett,
Federal Register Liaison Officer, U.S. Department of Energy.
[FR Doc. 2024-05462 Filed 3-13-24; 8:45 am]
BILLING CODE 6450-01-P