[Federal Register Volume 90, Number 12 (Tuesday, January 21, 2025)]
[Proposed Rules]
[Pages 6845-6852]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2025-00263]
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DEPARTMENT OF ENERGY
Federal Energy Regulatory Commission
18 CFR Part 40
[Docket No. RM25-3-000]
Reliability Standards for Frequency and Voltage Protection
Settings and Ride-Through for Inverter-Based Resources
AGENCY: Federal Energy Regulatory Commission.
ACTION: Notice of proposed rulemaking.
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SUMMARY: The Federal Energy Regulatory Commission (Commission) proposes
to approve proposed Reliability Standards PRC-024-4 (Frequency and
Voltage Protection Settings for Synchronous Generators, Type 1 and Type
2 Wind Resources, and Synchronous Condensers) and PRC-029-1 (Frequency
and Voltage Ride-through Requirements for Inverter-Based Resources),
which the North American Electric Reliability Corporation submitted in
response to Commission directives. The Commission seeks comments on all
aspects of the proposed approval.
DATES: Comments are due March 24, 2025.
ADDRESSES: Comments, identified by docket number, may be filed in the
following ways. Electronic filing through http://www.ferc.gov, is
preferred.
Electronic Filing: Documents must be filed in acceptable
native applications and print-to-PDF, but not in scanned or picture
format.
For those unable to file electronically, comments may be
filed by USPS mail or by hand (including courier) delivery.
[cir] Mail via U.S. Postal Service Only: Addressed to: Federal
Energy Regulatory Commission, Secretary of the Commission, 888 First
Street, NE, Washington, DC 20426.
[cir] Hand (including courier) delivery: Deliver to: Federal Energy
Regulatory Commission, 12225 Wilkins Avenue, Rockville, MD 20852.
FOR FURTHER INFORMATION CONTACT:
Syed Ahmad (Technical Information), Office of Electric Reliability,
Federal Energy Regulatory Commission, 888 First Street NE, Washington,
DC 20426, (202) 502 8718, [email protected]
Boris Voynik (Technical Information), Office of Electric Reliability,
Federal Energy Regulatory Commission, 888 First Street NE, Washington,
DC 20426, (202) 502 8902, [email protected]
Felicia West (Legal Information), Office of General Counsel, Federal
Energy Regulatory Commission, 888 First Street NE, Washington, DC
20426, (202) 502 8948, [email protected]
Hampden T. Macbeth (Legal Information), Office of General Counsel,
Federal Energy Regulatory Commission, 888 First Street NE, Washington,
DC 20426, (202) 502 8957, [email protected]
SUPPLEMENTARY INFORMATION:
1. Pursuant to section 215(d)(2) of the Federal Power Act (FPA),\1\
the Commission proposes to approve the addition of the newly defined
term ``Ride-through'' to the North American Electric Reliability
Corporation (NERC) Glossary of Terms and to approve the proposed
Protection and Control (PRC) Reliability Standards PRC-024-4 (Frequency
and Voltage Protection Settings for Synchronous Generators, Type 1 and
Type 2 Wind Resources, and Synchronous Condensers) \2\ and PRC-029-1
(Frequency and Voltage Ride-through Requirements for Inverter-Based
Resources (IBR)). We also propose to approve the associated violation
risk factors, violation severity levels,
[[Page 6846]]
implementation plans, and effective dates for proposed Reliability
Standards PRC-024-4 and PRC-029-1, as well as to approve the retirement
of currently effective Reliability Standard PRC-024-3.
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\1\ 16 U.S.C. 824o(d)(2).
\2\ Type 1 and type 2 wind resources are not inverter-based wind
turbine generators. Rather, type 1 and type 2 wind resources rely on
passive induction generators with limited ability to control active
power, reactive power, or voltage. NERC, Reliability Guideline:
Power Plant Model Verification for Inverter-Based Resources, vii, ix
(Sept. 2018), https://www.nerc.com/comm/RSTC_Reliability_Guidelines/PPMV_for_Inverter-Based_Resources.pdf.
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2. In Order No. 901, the Commission directed NERC to develop new or
modified Reliability Standards addressing, among other things,
reliability gaps associated with IBRs tripping or entering momentary
cessation in aggregate.\3\ Specifically, Order No. 901 directed NERC to
submit by November 4, 2024 new or modified Reliability Standards that
establish IBR performance requirements, including requirements
addressing frequency and voltage ride through, post disturbance ramp
rates, phase lock loop synchronization, and other known causes of IBR
tripping or momentary cessation.\4\
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\3\ Reliability Standards to Address Inverter-Based Resources,
Order No. 901, 88 FR 74250 (Oct. 30, 2023), 185 FERC ] 61,042
(2023).
\4\ Id. PP 7, 56, 190, 229.
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3. NERC submitted the proposed Reliability Standards in response to
Commission directives in Order No. 901.\5\ The purpose of proposed
Reliability Standard PRC-024-4 ``is to ensure that protection of
synchronous generators, type 1 and type 2 wind resources, and
synchronous condensers do not cause tripping during defined frequency
and voltage excursions in support'' of the Bulk-Power System.'' \6\ The
purpose of proposed Reliability Standard PRC-029-1 is to ``ensure that
IBRs Ride-through disturbances to support the Bulk-Power System . . .
during and after defined frequency and voltage excursions.'' \7\ We
seek comments on all aspects of the proposed approvals.
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\5\ See generally supra n.3.
\6\ NERC Petition at 51.
\7\ Id. at 24. The Bulk-Power System is defined in the FPA as
facilities and control systems necessary for operating an
interconnected electric energy transmission network (or any portion
thereof); and electric energy from generating facilities needed to
maintain transmission system reliability. The term does not include
facilities used in the local distribution of electric energy. 16
U.S.C. 824o(a)(1).
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4. We propose to find that proposed Reliability Standards PRC-024-4
and PRC-029-1 are consistent with and responsive to applicable
directives in Order No. 901 in requiring generator owners of IBRs to
ride through frequency and voltage excursions, such as a fault on the
transmission or sub-transmission system.
5. In addition, we propose to direct NERC to develop and submit two
informational filings 12 months and 24 months after the conclusion of
NERC's proposed 12-month exemption request period for existing IBRs.
Proposed Reliability Standard PRC-029-1 includes a provision that
allows existing IBRs that are already in operation when proposed
Reliability Standard PRC-029-1 goes into effect (legacy IBRs) to obtain
an exemption to the voltage and frequency Ride-through requirements if
hardware replacements would be necessary to comply. The Commission
seeks to understand the volume of exemptions, the circumstances in
which entities have invoked the exemption provision, and ultimately to
understand what if any effect the exemption provision has on the
efficacy of Reliability Standard PRC-029-1. Therefore, we propose to
direct that NERC submit two informational filings that provide details
on requested exemptions from generator owners of legacy IBRs for
frequency and/or voltage Ride-through requirements.
I. Background
A. Section 215 and Mandatory Reliability Standards
6. Section 215 of the FPA provides that the Commission may certify
an Electric Reliability Organization (ERO), the purpose of which is to
develop mandatory and enforceable Reliability Standards, subject to
Commission review and approval.\8\ Reliability Standards may be
enforced by the ERO, subject to Commission oversight, or by the
Commission independently.\9\ Pursuant to section 215 of the FPA, the
Commission established a process to select and certify an ERO,\10\ and
subsequently certified NERC.\11\
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\8\ 16 U.S.C. 824o(c).
\9\ Id. 824o(e).
\10\ Rules Concerning Certification of the Elec. Reliability
Org.; & Procs. for the Establishment, Approval, & Enforcement of
Elec. Reliability Standards, Order No. 672, 114 FERC ] 61,104, order
on reh'g, Order No. 672-A, 114 FERC ] 61,328 (2006); see also 18 CFR
39.4(b) (2024).
\11\ N. Am. Elec. Reliability Corp., 116 FERC ] 61,062, order on
reh'g & compliance, 117 FERC ] 61,126 (2006), aff'd sub nom. Alcoa,
Inc. v. FERC, 564 F.3d 1342 (D.C. Cir. 2009).
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B. Order No. 901
7. In Order No. 901, the Commission explained, among other things,
that the majority of installed IBRs use grid-following inverters, which
can track grid state parameters (e.g., voltage angle) in milliseconds
and react nearly instantaneously to changing grid conditions.\12\ The
Commission then explained that, as found by multiple NERC reports,\13\
some IBRs ``are not configured or programmed to support grid voltage
and frequency in the event of a system disturbance, and, as a result,
will reduce power output, exhibit momentary cessation, or trip in
response to variations in system voltage or frequency.'' \14\
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\12\ Order No. 901, 185 FERC ] 61,042 at P 12.
\13\ Id. P 26 n.53 (listing 12 NERC reports describing IBR
behavior during disturbances).
\14\ Id. P 12 (footnotes omitted).
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8. In addition, the Commission explained that IBRs across the Bulk-
Power System exhibit common mode failures that are amplified when IBRs
act in the aggregate.\15\ ``IBRs that enter momentary cessation may act
in aggregate and cause a reduction in power output far in excess of any
individual IBR's impact on the Bulk-Power System.'' \16\ The Commission
emphasized that the anticipated growth of IBRs would exacerbate these
reliability concerns.\17\
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\15\ Id. P 13.
\16\ Id.
\17\ Id.
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9. Therefore, the Commission directed NERC to develop new or
modified Reliability Standards pertaining to IBRs in four areas: (1)
data sharing; (2) model validation; (3) planning and operational
studies; and (4) performance requirements.\18\ The Commission required
NERC to submit by November 4, 2024 new or modified Reliability
Standards that require registered IBR generator owners and operators to
use appropriate settings ``to ride through frequency and voltage system
disturbances and that permit IBR tripping only to protect the IBR
equipment in scenarios similar to when synchronous generation resources
use tripping as protection from internal faults.'' \19\
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\18\ E.g., id. PP 1, 5, 53.
\19\ Id. PP 7, 190.
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10. The Commission mandated that the new or modified ride through
Reliability Standards must require registered IBRs to continue to
inject current and perform frequency support during Bulk-Power System
disturbances. Additionally, the new or modified Reliability Standards
must assure that registered IBR generator owners and operators continue
to inject energy into the electric grid during disturbances, within an
established no-trip zone. Finally, the Commission directed that the new
or modified Reliability Standards must establish requirements for
frequency and voltage ride through, post disturbance ramp rates, phase
lock loop synchronization, and other known causes of IBR tripping or
momentary cessation.\20\
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\20\ Id. P 190.
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11. The Commission also recognized that some older IBRs may have
hardware limitations that IBR owners would have to physically replace
and
[[Page 6847]]
may have settings and configurations that IBR owners could not modify
through software updates and in such circumstances could not implement
voltage ride through performance requirements. Thus, the Commission
directed NERC to ``determine whether the new or modified Reliability
Standards should provide for a limited and documented exemption for
certain registered IBRs from voltage ride through performance
requirements.'' \21\ The Commission added that if NERC determined that
an exemption is appropriate, the new or modified Reliability Standards
should mitigate the reliability impacts to the Bulk-Power System of
such an exemption.\22\
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\21\ Id. P 193.
\22\ Id. P 199.
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II. NERC Petition
12. On November 4, 2024,\23\ in response to Order No. 901, NERC
submitted for Commission approval the proposed definition of the term
Ride-through for the NERC Glossary of Terms, proposed Reliability
Standards PRC-024-4 and PRC-029-1, the associated violation risk
factors and violation severity levels, implementation plans and
effective dates for Reliability Standards PRC-024-4 and PRC-029-1, and
the retirement of currently effective Reliability Standard PRC-024-
3.\24\ NERC asserts that proposed Reliability Standards PRC-024-4 and
PRC-029-1 would ensure that applicable Bulk-Power System-connected
resources Ride-through system disturbances, avoiding reliability risks
associated with unnecessary tripping and momentary cessation.\25\
According to NERC, proposed Reliability Standard PRC-029-1 addresses 13
of the Order No. 901 directives.\26\
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\23\ Following the issuance of Order No. 901, NERC submitted an
informational filing that included its Order No. 901 Work Plan with
four key milestones for meeting the directives of Order No. 901.
Milestone 1: submit Work Plan (completed Jan. 17, 2024). Milestone
2: submit new or modified Reliability Standards to address
performance requirements and post-event performance validation for
registered IBRs (completed with NERC's filing of three petitions on
Nov. 4, 2024). Milestone 3: submit new or modified Reliability
Standards to address data sharing and model validation by Nov. 4,
2025. Milestone 4: submit new or modified Reliability Standards to
address planning and operational studies requirements for all IBRs
by Nov. 4, 2026. NERC, Informational Filing Regarding the
Development of Reliability Standards Responsive to Order No. 901,
Docket No. RM22-12-000, at 6 (filed Jan. 17, 2024).
\24\ NERC Petition at 2-3, 5. Proposed Reliability Standards
PRC-024-4 and PRC-029-1 are not attached to this notice of proposed
rulemaking. The proposed Reliability Standards are available on the
Commission's eLibrary document retrieval system in Docket No. RM25-
3-000 and on the NERC website, www.nerc.com.
\25\ Id. at 1, 19.
\26\ Id. Ex. D (Standards Development Consideration of
Directives from FERC Order No. 901).
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A. Addition of Defined Term Ride-Through to NERC Glossary of Terms
13. NERC states that proposed Reliability Standard PRC-029-1 uses
the term Ride-through, which NERC proposes to include in the NERC
Glossary of Terms. NERC explains that the term Ride-through would mean
that ``the plant/facility remains connected and continues to operate
through voltage or frequency system disturbances.'' \27\
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\27\ Id. at 23.
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B. Proposed Reliability Standard PRC-024-4
14. NERC explains that proposed Reliability Standard PRC-024-4
removes language relating to IBR functionality in Requirements R1, R2,
R3, and R4 because IBR performance requirements are included in
proposed Reliability Standard PRC-029-1. Instead, proposed Reliability
Standard PRC-024-4 would maintain capability-based requirements for
synchronous generators, synchronous condensers, and type 1 and type 2
wind resources.\28\ NERC also notes that, consistent with the proposed
definition for IBRs in the NERC Glossary of Terms,\29\ type 1 and type
2 wind resources, which operate as asynchronous resources and lack
modern controllers capable of riding through system events as they do
not have a power electronic device, are not considered IBRs.\30\
Moreover, NERC explains that, because synchronous units do not require
performance-based requirements to Ride-through system disturbances,
proposed Reliability Standard PRC-024-4 would continue to address Ride-
through compatible frequency and voltage protection setting ranges for
synchronous generators, synchronous condensers, and type 1 and type 2
wind resources.\31\
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\28\ Id. at 15.
\29\ On November 4, 2024, NERC concurrently filed along with
other Milestone 2 Reliability Standards, a petition with the
Commission for approval of its proposed definition for IBR as:
A plant/facility consisting of individual devices that are
capable of exporting Real Power through a power electronic
interface(s) such as an inverter or converter, and that are operated
together as a single resource at a common point of interconnection
to the electric system. Examples include, but are not limited to,
plants/facilities with solar photovoltaic (PV), Type 3 and Type 4
wind, battery energy storage system (BESS), and fuel cell devices.
NERC, Petition for Approval of a New Term ``Inverter-Based
Resource'' Used in NERC Reliability Standards, Docket No. RD25-1-
000, at 1 (filed Nov. 4, 2024) (IBR Definition), currently pending
before the Commission.
\30\ NERC Petition at 49. See IBR Definition.
\31\ NERC Petition at 49.
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15. NERC also includes minor edits in proposed Reliability Standard
PRC-024-4 to maintain the Standard's frequency and voltage protection
capability-based requirements for synchronous resources. Specifically,
NERC modified section 4.1.1 to restrict the applicability of proposed
Reliability Standard PRC-024-4 to synchronous generators and type 1 and
type 2 wind resources, and NERC added section 4.2.2 to include
synchronous condensers and associated equipment as applicable
facilities.\32\ Further, NERC modified Requirements R1, R2, R3, and R4
to apply to transmission owners that apply frequency, voltage, and
volts per hertz protection for their synchronous condensers.
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\32\ Id. at 51.
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C. Proposed Reliability Standard PRC-029-1
16. NERC explains that proposed Reliability Standard PRC-029-1
would address directives in Order No. 901 by establishing frequency and
voltage Ride-through performance requirements for generator owners of
IBRs.
1. Proposed Requirement R1
17. Under proposed Requirement R1 each generator owner of a NERC-
registered IBR must ``ensure the design and operation is such that each
IBR meets or exceeds Ride-through requirements, in accordance with the
`must Ride-through zone' as specified in Attachment 1'' of proposed
Reliability Standard PRC-029-1, except in the following four conditions
specified by the Standard: \33\
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\33\ Id. at 25.
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The IBR needed to electrically disconnect in order to
clear a fault;
The voltage at the high-side of the main power transformer
went outside an accepted hardware limitation, in accordance with
Requirement R4;
The instantaneous positive sequence voltage phase angle
change is more than 25 electrical degrees at the high-side of the main
power transformer and is initiated by a non-fault switching event on
the transmission system; or
The Volts per Hz (V/Hz) at the high-side of the main power
transformer exceed 1.1 per unit for longer than 45 seconds or exceed
1.18 per unit for longer than 2 seconds.\34\
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\34\ Id. at 26.
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18. NERC explains that it adopted the Institute of Electrical and
Electronics Engineers (IEEE) standard 2800-2022's (IEEE 2800-2022)
terminology for ``must
[[Page 6848]]
ride-through zones,'' which are defined in terms of voltage and
frequency magnitude and time duration.\35\ NERC explains that it
considered but ultimately rejected Ride-through criteria more stringent
than set forth in IEEE 2800-2022 due to industry comments raised during
the IBR technical conference conveyed by NERC.\36\ But, NERC adds, the
must Ride-through zones in proposed Requirement R1 are ``more similar''
to IEEE 2800-2022's Ride-through zones, are more robust than currently
effective PRC-024-3, and are sufficient to address the recommendations
NERC identified in response to reports and assessments analyzing IBR
loss of power events.\37\
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\35\ Id. at 27.
\36\ Following the failure of the third ballot on proposed
Reliability Standard PRC-024-4 and proposed Reliability Standard
PRC-029-1, NERC convened a public technical conference under section
321 of the NERC Rules of Procedure to discuss issues surrounding the
Order No. 901 directives. Id. at 7. Section 321 of the NERC Rules of
Procedure allows the NERC Board of Trustees to take special actions
when a ballot pool has ``failed to approve a proposed Reliability
Standard that contains a provision to adequately address a specific
matter identified in a directive issued'' by the Commission. NERC,
Rules of Procedure, Sec. 321 (Nov. 28, 2023), https://www.nerc.com/AboutNERC/RulesOfProcedure/NERC%20ROP%20effective%2020240627_with%20appendicies_signed.pdf.
\37\ NERC Petition at 27-28.
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19. NERC asserts that proposed Requirement R1 is responsive to the
directive that NERC develop performance-based Reliability Standards
that require IBRs to ride through voltage system disturbances and
require post-disturbance ramp rates to return to pre-disturbance
levels.\38\ Similarly, NERC avers that proposed Requirement R1 is
consistent with the directive that IBRs inject current and perform
frequency support during a disturbance by requiring IBRs remain
connected and fulfill control and regulation functions to Ride-through
a system disturbance.\39\ Additionally, NERC asserts that the provision
in proposed Requirement R1 requiring IBRs to meet or exceed Ride-
through requirements in Attachment 1 of proposed Reliability Standard
PRC-029-1 that restricts the use of momentary cessation satisfies the
directive to prohibit momentary cessation in the no-trip zone during
disturbances.\40\
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\38\ Id. at 42.
\39\ Id.
\40\ Id. at 42-43.
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2. Proposed Requirement R2
20. Under proposed Requirement R2, each generator owner of a NERC-
registered IBR must adhere to voltage Ride-through performance criteria
during system disturbances unless a documented hardware limitation
exists in accordance with Requirement R4.\41\ Similar to Requirement
R1, NERC asserts that proposed Requirement R2 satisfies the following
directives: (1) that NERC develop performance-based Reliability
Standards that require IBRs to ride through voltage system
disturbances; and (2) that IBRs inject current and perform frequency
support during a disturbance by requiring IBRs remain connected and
fulfill control and regulation functions to Ride-through a system
disturbance.\42\
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\41\ Id. at 29-33.
\42\ Id. at 42.
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3. Proposed Requirement R3
21. Under proposed Requirement R3, each generator owner of a NERC-
registered IBR must ensure that its IBR adheres to Ride-through
requirements during frequency excursion events by continuing to
exchange current and remain electrically connected in accordance with
the ``must ride-through zone'' as specified in the proposed Reliability
Standard's Attachment 2 and while the ``absolute rate of change of
frequency (RoCoF) magnitude is less than or equal to 5 Hz/second,
unless a documented hardware limitation exists in accordance with
Requirement R4.'' \43\ NERC explains that proposed Requirement R3
contains a wider frequency Ride-through band than presently exists in
Reliability Standard PRC-024-3 and is consistent with IEEE 2800-
2022.\44\
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\43\ Id. at 33.
\44\ Id. at 36.
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22. NERC asserts that proposed Requirement R3 is responsive to the
directive that NERC develop performance-based Reliability Standards
that require IBRs to ride through frequency system disturbances.\45\
Additionally, NERC contends that proposed Requirement R3 satisfies the
directive that IBRs inject current and perform frequency support during
a disturbance by requiring IBRs remain connected and fulfill control
and regulation functions to Ride-through a system disturbance.\46\
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\45\ Id. at 42.
\46\ Id.
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4. Proposed Requirement R4
23. Proposed Requirement R4 would allow each generator owner of an
existing legacy IBR, i.e., one in service by the effective date of PRC-
029-1, to obtain an exemption to the voltage and frequency Ride-through
requirements if the generator owner would need hardware replacements to
comply with Requirements R1 through R3. Specifically, Requirement R4
provides that ``[e]ach Generator Owner identifying an IBR that is in-
service by the effective date of PRC-029-1, has known hardware
limitations that prevent the IBR from meeting Ride-through criteria as
detailed in Requirements R1-R3, and requires an exemption from specific
Ride-through criteria shall . . . [d]ocument information supporting the
identified hardware limitation. . . .'' \47\ Each generator owner of an
IBR must provide the information (unless it is considered proprietary
by the original equipment manufacturer) to each planning coordinator,
transmission planner, transmission operator, and reliability
coordinator in the footprint in which the legacy IBR is located.\48\
Moreover, the generator owner must submit documentation to the relevant
Compliance Enforcement Authority--typically a Regional Entity--that
``must accept that all aspects of the documentation specified in
proposed Requirement R4 have been provided by the Generator Owner
before an exemption can [be] granted.'' \49\ According to NERC, this
last requirement ``would ensure that NERC has visibility into each
hardware exemption that is granted and that [it has] been accurately
limited to the particular limitation of the hardware.'' \50\
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\47\ Id. at 36-37.
\48\ Id. at 37.
\49\ Id. at 40.
\50\ Id.
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24. NERC explains that it determined that an exemption process for
generator owners of legacy IBRs for voltage and frequency performance
requirements is necessary. In its petition, NERC expressed concern that
hardware limitations would lead entities to take units offline to
retrofit IBRs or risk noncompliance and could determine that the
economically prudent course of action is to retire the units.\51\ The
implementation plan gives generator owners 12 months to request an
exemption following the effective date of the Reliability Standard,
after which NERC will not accept further exemption requests.\52\ If the
hardware causing the limitation is replaced later, the generator owner
must communicate this information to the planning coordinator,
transmission planner, reliability coordinator, and transmission
operator within 90 days of the hardware replacement and comply with
Requirements R1 through R3.\53\ Further,
[[Page 6849]]
NERC explains that the exemptions must be specific and limited to the
voltage or frequency bands and associated duration that cannot be
satisfied or as to the number of cumulative voltage deviations within a
ten-second period that the equipment can Ride-through if it is less
than four deviations within any ten-second period.\54\
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\51\ Id. at 38.
\52\ Id. at 37.
\53\ Id. at 41.
\54\ Id. at 39.
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25. NERC asserts that proposed Requirement R4 meets the directive
that NERC determine whether the new or modified Reliability Standards
provide an opportunity for certain generator owners of IBRs that are
currently in operation and unable to meet performance requirements to
request an exemption from voltage ride-through performance
requirements.\55\ NERC determined that a frequency exemption was also
necessary and appropriate because of hardware-based capability
limitations for a significant amount of installed IBRs, a concern that
was raised during the IBR technical conference convened by NERC.\56\
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\55\ Id. at 44.
\56\ Id. at 38-39.
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26. Regarding the Commission directive to NERC to develop new or
modified Reliability Standards to mitigate the reliability impacts to
the Bulk-Power System of approved exemptions, NERC claims that the
reliability impacts of voltage and frequency ride-through exemptions
are mitigated by existing Reliability Standards that address the
responsibilities of transmission planners, planning coordinators,
reliability coordinators, and transmission operators.\57\ Moreover,
under Milestone 4 of the Order No. 901 Work Plan,\58\ NERC indicates
that it ``will develop Reliability Standards that will specifically
require evaluations that include accurately-modeled performance
capabilities of IBRs, inclusive of any documented Ride-through criteria
exemption accepted through the process detailed in proposed Reliability
[Standard] PRC-029-1 Requirement R4, and that evaluate for reliability
impacts'' on the Bulk-Power System.\59\
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\57\ Id. at 46. See also id. n.67 (providing as examples
existing Reliability Standards IRO-002-7 (Reliability Coordination--
Monitoring and Analysis), IRO-008-3 (Reliability Coordinator
Operational Analyses and Real-time Assessments), TOP-002-4
(Operations Planning), and TPL-001-5.1 (Transmission System Planning
Performance Requirements)).
\58\ See supra note 23 for more information on the elements of
the Order No. 901 Work Plan's milestones.
\59\ NERC Petition at 46.
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III. Discussion
27. Pursuant to section 215(d)(2) of the FPA, the Commission
proposes to approve the proposed definition of Ride-through and
proposed Reliability Standards PRC-024-4 and PRC-029-1 as just,
reasonable, not unduly discriminatory or preferential, and in the
public interest. We also propose to approve the associated violation
risk factors, violation severity levels, implementation plans, and
effective dates of Reliability Standards PRC-024-4 and PRC-029-1, as
well as to approve the retirement of currently effective Reliability
Standard PRC-024-3.
28. We propose to find that the proposed Reliability Standards are
consistent with the performance requirement directives of Order No. 901
as generator owners of NERC-registered IBRs will be subject to the
Ride-through performance requirements of proposed Reliability Standard
PRC-029-1 unless exempted under that standard. The Commission seeks
comments on all aspects of these proposals.
A. Proposal To Approve the Addition of Defined Term Ride-Through to
NERC Glossary of Terms
29. NERC's proposed definition of the term Ride-through for
inclusion in the NERC Glossary of Terms should provide a clear and
consistent understanding of the term across all Reliability Standards,
including proposed new or modified Reliability Standards filed with the
Commission in response to various Order No. 901 directives. We
therefore propose to approve the proposed definition of the term Ride-
through for inclusion in the NERC Glossary of Terms.
B. Proposal To Approve Proposed Reliability Standard PRC-024-4
30. Proposed Reliability Standard PRC-024-4 should maintain the
Reliability Standard's frequency and voltage protection setting
requirements as applicable to only synchronous generators, type 1 and 2
wind resources, and synchronous condensers. Specifically, synchronous
generators, type 1 and 2 wind resources, and synchronous condensers
will have to have voltage and frequency protection set to avoid
tripping during defined frequency and voltage excursions. We believe
that it is reasonable to remove references to IBRs in proposed
Reliability Standard PRC-024-4 as IBRs would be subject to the Ride-
through requirements in proposed Reliability Standard PRC-029-1.
31. Therefore, we propose to approve proposed Reliability Standard
PRC-024-4 as just, reasonable, not unduly discriminatory or
preferential, and in the public interest. We seek comments on all
aspects of our proposed approval of proposed Reliability Standard PRC-
024-4.
C. Proposal To Approve Proposed Reliability Standard PRC-029-1
32. We propose to find that the proposed Reliability Standard PRC-
029-1 responds to the relevant Order No. 901 Ride-through performance
requirement directives. The Ride-through provisions of proposed
Requirements R1 through R3 would require that each generator owner of a
NERC-registered IBR ensure that their IBR continues to inject current
and perform frequency support during a Bulk-Power System disturbance
and avoids momentary cessation in the no-trip zone during a disturbance
by meeting or exceeding the Ride-through requirements. Further, these
proposed provisions establish specific requirements for frequency and
voltage Ride-through, post-disturbance ramp rates, phase lock loop
synchronization, and other known causes of IBR tripping or momentary
cessation. The Ride-through requirements of proposed Requirements R1
through R3 should strengthen the reliability of the Bulk-Power System
by ensuring that IBRs are designed and operated to remain connected to
the Bulk-Power system and continue to inject real and/or reactive
current during system disturbances.
33. The Commission proposes to find that NERC reasonably determined
that an exemption process for generator owners of legacy IBRs for
voltage and frequency performance requirements as set out in
Requirement R4 is appropriate based on industry input during the
standards drafting process, as explained in the NERC Petition.\60\
Regarding whether NERC met the Order No. 901 directive to develop new
or modified Reliability Standards to mitigate the reliability impacts
to the Bulk-Power System of such exemptions, we will defer our
determination until after NERC files Milestone 4 Reliability Standards
with the Commission by November 4, 2026. As described by NERC's
petition, NERC is planning to meet this mitigation directive with its
anticipated approach to Milestone 4 Reliability Standards that will
require accurate modeling of IBRs' performance capabilities, including
accepted Ride-through criteria exemptions, and
[[Page 6850]]
evaluate reliability impacts on the Bulk-Power System.\61\
---------------------------------------------------------------------------
\60\ Id. at 38-41.
---------------------------------------------------------------------------
34. The Commission seeks comments on its proposed approval of
proposed Reliability Standard PRC-029-1. While we seek comments on all
aspects of the proposed Reliability Standard, we are particularly
interested in comments and supporting materials, where applicable, on
concerns regarding: (1) the IBR performance requirement set forth in
Requirement R1; (2) the absolute RoCoF in Requirement R3; and (3) the
adequacy of NERC's proposed exemption provision in Requirement R4 as it
pertains to both projects in service and those under contract, but not
yet in-service as of the effective date of Reliability Standard PRC-
029-1. Comments on whether the exemption provision is too broad or too
narrow should address the risks and benefits of expanding or narrowing
the exemption provision and should provide detailed, quantified, and
fact-based support for their position.
---------------------------------------------------------------------------
\61\ Id. at 46.
---------------------------------------------------------------------------
D. Proposed Directive for Informational Filings
35. Finally, we propose to direct NERC to develop and submit two
informational filings pertaining to requests for exemption by generator
owners of legacy IBRs from frequency and/or voltage Ride-through
requirements. While we understand the appropriateness of a limited
exemption for certain legacy equipment that may otherwise not be able
to comply with the proposed Ride-through requirements, we are concerned
about the practical implications of the exemptions as proposed.
Specifically, if too many generators are exempt from the frequency and/
or voltage Ride-through requirements, proposed Reliability Standard
PRC-029-1 may fail to address the reliability gaps associated with IBRs
tripping or entering momentary cessation in aggregate that it is
intended to address.\62\ Accordingly, we propose that 12 months and 24
months after the conclusion of the 12-month exemption request period,
NERC submit an informational filing with the following data for (1)
each Interconnection and (2) each reliability coordinator area (within
that interconnection) within the United States:
---------------------------------------------------------------------------
\62\ See, e.g., Order No. 901, 185 FERC ] 61,042 at PP 1, 13,
190.
---------------------------------------------------------------------------
Total number of IBRs for which NERC-registered generator
owners will be subject to compliance with Reliability Standard PRC-029-
1;
Aggregated megawatts (MW) capacity of IBRs for which NERC-
registered generator owners will be subject to compliance with
Reliability Standard PRC-029-1;
Total number of IBRs for which NERC-registered generator
owners requested exemptions;
Aggregated MW capacity of IBRs for which NERC-registered
generator owners requested exemptions;
Total number of IBRs for which NERC-registered generator
owners were granted exemptions;
Aggregated MW capacity of IBRs for which NERC-registered
generator owners were granted exemptions;
Total number of granted exemptions by exemption type
(voltage and/or frequency);
Aggregated MW capacity of granted exemptions by exemption
type (voltage and/or frequency);
Total number of granted exemptions by IBR type (wind,
solar PV, BESS, fuel cell); and
Aggregated MW capacity of granted exemptions by IBR type
(wind, solar PV, BESS, fuel cell).
Additionally, we propose that each informational filing include an
analysis of the reasons that entities provided for exemptions (both
granted and denied),\63\ an evaluation of the efficacy of the exemption
process, and any recommendations to modify either the substance or
procedural aspects.
---------------------------------------------------------------------------
\63\ NERC Petition at 40 (explaining that under Requirement
R4.2.2, NERC will work with regional entities to evaluate exemption
submissions in a fair and consistent manner across the ERO
Enterprise and NERC will monitor the disposition of requests as the
proposed standard is implemented).
---------------------------------------------------------------------------
IV. Information Collection Statement
36. The FERC-725G information collection requirements are subject
to review by the Office of Management and Budget (OMB) under section
3507(d) of the Paperwork Reduction Act of 1995. OMB's regulations
require approval of certain information collection requirements imposed
by agency rules. Upon approval of a collection of information, OMB will
assign an OMB control number and expiration date. Respondents subject
to the filing requirements will not be penalized for failing to respond
to these collections of information unless the collections of
information display a valid OMB control number. The Commission solicits
comments on the need for this information, whether the information will
have practical utility, the accuracy of the burden estimates, ways to
enhance the quality, utility, and clarity of the information to be
collected or retained, and any suggested methods for minimizing
respondents' burden, including the use of automated information
techniques.
37. The Commission bases its paperwork burden estimates on the
additional paperwork burden presented by the proposed Reliability
Standards PRC-024-4 and PRC-029-1, as modified and new Reliability
Standards, respectively, and the proposed directive for NERC to submit
two informational filings related to Ride-through exemption
requests.\64\ Reliability Standards are objective-based and allow
entities to choose compliance approaches best tailored to their
systems. The NERC Compliance Registry, as of September 2024, identifies
the following unique U.S. entities that are subject to mandatory
compliance with Reliability Standard PRC-024-4: 1,230 generator owners
will have an additional compliance burden. It is estimated that there
will be no additional compliance burden for transmission owners that
have synchronous condensers, as that data is not included in the NERC
Compliance Registry, and transmission owners are already applicable to
PRC-024-4. The estimated unique U.S. entities subject to Reliability
Standard PRC-029-1 compliance are based on numbers supplied by NERC,
with 591 registered generator owners that own bulk electric system
(BES) solar and wind facilities and a median of 755 generator owners
that own non-BES facilities.\65\ Based on these assumptions, we
estimate the following reporting burden:
---------------------------------------------------------------------------
\64\ See supra P 35.
\65\ NERC estimates that 591 BES IBRs and a range of 588 to 922
non-BES IBRs, with a median of 755, will be subject to proposed
Reliability Standard PRC-029-1 and the other Milestone 2 Reliability
Standards that were filed in Docket Nos. RD25-2-000 and RD25-3-000.
See NERC, Petition For Approval of Proposed Distribution Monitoring
Reliability Standards PRC-028-1 and PRC-002-5, Docket No. RD25-2-
000, at 41 n.60 (filed Nov. 4, 2024) (description of NERC estimates
of BES IBRs and the range of non-BES IBRs that would be subject to
compliance with proposed Reliability Standard PRC-028-1).
[[Page 6851]]
Proposed Changes in Burden PRC-024-4 Docket No. RM25-3-000
--------------------------------------------------------------------------------------------------------------------------------------------------------
Number of
Type and number of annual Total number Average number of burden
Reliability standard entity \66\ responses per of responses hours per response \67\ Total burden hours
entity
--------------------------------------------------------------------------------------------------------------------------------------------------------
(1)................ (2) (1) * (2) = (4)......................... (3) * (4) = (5)
(3)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Annual Collection PRC024-4 FERC-725G
--------------------------------------------------------------------------------------------------------------------------------------------------------
Annual review and record 1,230 (GO)......... 1 1,230 20 hrs. $70.67/hr........... 24,600 hrs. $1,738,482
retention.
--------------------------------------------------------------------------------------------------
Total for PRC-024-4......... ................... ............... 1,230 20 hrs. $70.67/hr........... 24,600 hrs. $1,738,482
--------------------------------------------------------------------------------------------------------------------------------------------------------
Proposed Burden PRC-029-1 Docket No. RM25-3-000
--------------------------------------------------------------------------------------------------------------------------------------------------------
Number of
Type and number of annual Total number Average number of burden
Reliability standard entity \68\ responses per of responses hours per response \69\ Total burden hours
entity
--------------------------------------------------------------------------------------------------------------------------------------------------------
(1)................ (2) (1) * (2) = (4)......................... (3) * (4) = (5)
(3)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Annual Collection PRC-029-1 FERC-725G
--------------------------------------------------------------------------------------------------------------------------------------------------------
Annual review and record 591 (BES IBR GO)... 1 591 40 hrs. $70.67/hr........... 23,640 hrs. $1,670,638.80
retention.
755 (Non-BES IBR 1 755 80 hrs. $70.67/hr........... 60,400 hrs. $4,268,468.00
GO).
--------------------------------------------------------------------------------------------------
Total for PRC-024-4......... ................... ............... 1,346 ............................ 84,040 hrs. $5,939,106.80
--------------------------------------------------------------------------------------------------------------------------------------------------------
38. The responses and burden hours for Years 1-3 will total
respectively as follows:
---------------------------------------------------------------------------
\66\ The ``Number of Entity'' data is compiled from the
September 24, 2024, edition of the NERC Compliance Registry.
\67\ The estimated hourly cost (salary plus benefits) is a
combination of the following categories from the Bureau of Labor
Statistics (BLS) website, http://www.bls.gov/oes/current/naics2_22.htm: 75% of the average of an Electrical Engineer (17-
2071) $79.31/hr., 79.31 x .75 = 59.4825 ($59.48-rounded) ($59.48/
hour); and 25% of an Information and Record Clerk (43-4199) $44.74/
hr., $44.74 x .25% = 11.185 ($11.19 rounded) ($11.19/hour), for a
total ($59.48+$11.19 = $70.67/hour).
\68\ The ``Number of Entity'' data is compiled from NERC's
petition for approval of proposed Reliability Standard PRC-028-1 in
Docket No. RD25-2-000. NERC, Petition For Approval of Proposed
Distribution Monitoring Reliability Standards PRC-028-1 and PRC-002-
5, Docket No. RD25-2-000, at 41 n.60 (filed Nov. 4, 2024).
\69\ The estimated hourly cost (salary plus benefits) is a
combination of the following categories from the Bureau of Labor
Statistics (BLS) website, http://www.bls.gov/oes/current/naics2_22.htm: 75% of the average of an Electrical Engineer (17-
2071) $79.31/hr., 79.31 x .75 = 59.4825 ($59.48-rounded) ($59.48/
hour); and 25% of an Information and Record Clerk (43-4199) $44.74/
hr., $44.74 x.25% = 11.185 ($11.19 rounded) ($11.19/hour), for a
total ($59.48+$11.19 = $70.67/hour).
---------------------------------------------------------------------------
Year 1-3 each: for proposed Reliability Standard PRC-024-4
will be 1,230 responses; 24,600 hours; and
Year 1-3 each: for proposed Reliability Standard PRC-029-1
will be 1,346 responses; 84,040 hours.
The annual cost burden for each year One to Three is
$1,738,482 for proposed Reliability Standard PRC-024-4; and
$5,939,106.80 for proposed Reliability Standard PRC-029-1.
39. Title: Mandatory Reliability Standards, Revised Protection and
Control Reliability Standards
Action: Revision to FERC-725G information collection.
OMB Control No.: 1902-0281.
Respondents: Businesses or other for-profit institutions; not-for-
profit institutions.
Frequency of Responses: On Occasion.
Necessity of the Information: This notice of proposed rulemaking
proposes to approve the requested modifications to Reliability
Standards pertaining to the protection and control of the Bulk-Power
System. As discussed above, the Commission proposes to approve proposed
Reliability Standards PRC 024-4 and PRC-029-1 pursuant to section
215(d)(2) of the FPA because it establishes frequency and voltage Ride-
through requirements for IBRs. Additionally, the Commission proposes to
direct NERC to file two informational filings with the Commission on
Ride-through exemption requests.
Internal Review: The Commission has reviewed the proposed
Reliability Standards and made a determination that its action is
necessary to implement section 215 of the FPA.
Interested persons may obtain information on the reporting
requirements by contacting the following: Federal Energy Regulatory
Commission, 888 First Street NE, Washington, DC 20426 [Attention: Kayla
Williams, Office of the Executive Director, email:
[email protected], phone: (202) 502-8663, fax: (202) 273-0873].
40. For submitting comments concerning the collection(s) of
information and the associated burden estimate(s), please send your
comments to the Commission, and to the Office of Management and Budget,
Office of Information and Regulatory Affairs, Washington, DC 20503
[Attention: Desk Officer for the Federal Energy Regulatory Commission,
phone: (202) 395-4638, fax: (202) 395-7285]. For security reasons,
comments to OMB should be submitted by email to:
[email protected]. Comments submitted to OMB should include
Docket Number RM25-3-000 and OMB Control Number 1902-0281.
V. Environmental Analysis
41. The Commission is required to prepare an Environmental
Assessment or an Environmental Impact Statement for any action that may
have a significant adverse effect on the human environment.\70\ The
Commission has categorically excluded certain actions from this
requirement as not having a significant effect on the human
environment. Included in the exclusion are rules that are clarifying,
corrective, or procedural or that do not substantially change the
effect of the regulations being amended.\71\ The actions proposed
herein falls within this categorical exclusion in the Commission's
regulations.
---------------------------------------------------------------------------
\70\ Regulations Implementing the National Environmental Policy
Act, Order No. 486, 52 FR 47897 (Dec. 17, 1987), FERC Stats. & Regs.
] 30,783 (1987) (cross-referenced at 41 FERC ] 61,284).
\71\ 18 CFR 380.4(a)(2)(ii).
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[[Page 6852]]
VI. Regulatory Flexibility Act Certification
42. The Regulatory Flexibility Act of 1980 (RFA) \72\ generally
requires a description and analysis of proposed rules that will have
significant economic impact on a substantial number of small entities.
The Small Business Administration's (SBA) Office of Size Standards
develops the numerical definition of a small business.\73\ The SBA
revised its size standard for electric utilities (effective March 17,
2023) to a standard based on the number of employees, including
affiliates (from the prior standard based on megawatt hour sales).\74\
---------------------------------------------------------------------------
\72\ 5 U.S.C. 601-612.
\73\ 13 CFR 121.101.
\74\ 13 CFR 121.201, Subsector 221 (Utilities).
---------------------------------------------------------------------------
43. Proposed Reliability Standard PRC-024-4 (included in FERC-725G)
will apply to approximately 1,230 generator owners and proposed
Reliability Standard PRC-029-1 (included in FERC-725G) will apply to
approximately 1,346 BES/IBR combined generator owners and non-generator
owners in the United States.\75\ Pursuant to SBA regulations, the
employment threshold for generator owners is 950 employees. We estimate
that the percentage of employees that are considered small to be 74.59%
based on the North American Industry Classification System 221121 code
(Electric Bulk Power Generation) and that the annual cost for each
entity will be $1,413.40 for each generator owner and $2,826.80 for
each BES IBR generator owner and $5,653.60 for each Non-BES IBR
generator owner.
---------------------------------------------------------------------------
\75\ Many respondents serve multiple roles in the NERC
Compliance Registry, so there is likely double counting in the
estimates.
---------------------------------------------------------------------------
44. We view this as a minimal economic impact for each entity.
Accordingly, we certify that the proposed Reliability Standards PRC-
024-4 and PRC-029-1 will not have a significant economic impact on a
substantial number of small entities. Thus, no regulatory flexibility
analysis is required.
VII. Comment Procedures
45. The Commission invites interested persons to submit comments on
the matters and issues proposed in this notice to be adopted, including
any related matters or alternative proposals that commenters may wish
to discuss. Comments are due March 24, 2025. Comments must refer to
Docket No. RM25-3-000, and must include the commenter's name, the
organization they represent, if applicable, and their address in their
comments. All comments will be placed in the Commission's public files
and may be viewed, printed, or downloaded remotely as described in the
Document Availability section below. Commenters on this proposal are
not required to serve copies of their comments on other commenters.
46. The Commission encourages comments to be filed electronically
via the eFiling link on the Commission's website at http://www.ferc.gov. The Commission accepts most standard word processing
formats. Documents created electronically using word processing
software must be filed in native applications or print-to-PDF format
and not in a scanned format. Commenters filing electronically do not
need to make a paper filing.
47. Commenters that are not able to file comments electronically
may file an original of their comment by USPS mail or by courier-or
other delivery services. For submission sent via USPS only, filings
should be mailed to: Federal Energy Regulatory Commission, Office of
the Secretary, 888 First Street NE, Washington, DC 20426. Submission of
filings other than by USPS should be delivered to: Federal Energy
Regulatory Commission, 12225 Wilkins Avenue, Rockville, MD 20852.
VIII. Document Availability
48. In addition to publishing the full text of this document in the
Federal Register, the Commission provides all interested persons an
opportunity to view and/or print the contents of this document via the
internet through the Commission's Home Page (http://www.ferc.gov).
49. From the Commission's Home Page on the internet, this
information is available on eLibrary. The full text of this document is
available on eLibrary in PDF and Microsoft Word format for viewing,
printing, and/or downloading. To access this document in eLibrary, type
the docket number excluding the last three digits of this document in
the docket number field.
50. User assistance is available for eLibrary and the Commission's
website during normal business hours from FERC Online Support at (202)
502-6652 (toll free at 1-866-208-3676) or email at
[email protected], or the Public Reference Room at (202) 502-
8371, TTY (202) 502-8659. Email the Public Reference Room at
[email protected].
By direction of the Commission.
Issued: December 19, 2024.
Debbie-Anne A. Reese,
Secretary.
[FR Doc. 2025-00263 Filed 1-17-25; 8:45 am]
BILLING CODE 6717-01-P