Document ID: FERC-2022-0215-0001
Agency: ferc
Document Type: Notice
Title: Implementation of Dynamic Line Ratings
Posted Date: 2022-02-24T05:00Z

[Federal Register Volume 87, Number 37 (Thursday, February 24, 2022)]
[Notices]
[Pages 10349-10354]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2022-03911]

=======================================================================
-----------------------------------------------------------------------

DEPARTMENT OF ENERGY

Federal Energy Regulatory Commission

[Docket No. AD22-5-000]

Implementation of Dynamic Line Ratings

AGENCY: Federal Energy Regulatory Commission, DOE.

ACTION: Notice of inquiry.

-----------------------------------------------------------------------

SUMMARY: The Federal Energy Regulatory Commission (Commission) seeks 
comment on whether and how the required use of dynamic line ratings 
(DLR) is needed to ensure just and reasonable wholesale rates. The 
Commission further seeks comment on: Whether the lack of DLR 
requirements renders current wholesale rates unjust and unreasonable; 
potential criteria for DLR requirements; the benefits, costs, and 
challenges of implementing DLRs; the nature of potential DLR 
requirements; and potential timeframes for implementing DLR 
requirements.

DATES: Initial Comments are due April 25, 2022, and Reply Comments are 
due May 25, 2022.

ADDRESSES: Comments, identified by docket number, may be filed in the 
following ways. Electronic filing through http://www.ferc.gov is 
preferred.
     Electronic Filing through http://www.ferc.gov. Documents 
created electronically using word processing software must be filed in 
acceptable native applications or print-to-PDF format, but not in 
scanned or picture format.
     Mail/Hand Delivery: Those unable to file electronically 
may mail comments via the U.S. Postal Service to: Federal Energy 
Regulatory Commission, Secretary of the Commission, 888 First Street 
NE, Washington, DC 20426. Hand-delivered comments or comments sent via 
any other carrier should be delivered to: Federal Energy Regulatory 
Commission, 12225 Wilkins Avenue, Rockville, MD 20852.
     Instructions: For detailed instructions on submitting 
comments,

[[Page 10350]]

see the Comment Procedures Section of this document.

FOR FURTHER INFORMATION CONTACT: Daniel Kheloussi (Technical 
Information), Office of Energy Policy and Innovation, Federal Energy 
Regulatory Commission, 888 First Street NE, Washington, DC 20426, (202) 
502-6391, [email protected].
    Ryan Stroschein (Legal Information), Office of the General Counsel, 
Federal Energy Regulatory Commission, 888 First Street NE, Washington, 
DC 20426, (202) 502-8099, [email protected].

SUPPLEMENTARY INFORMATION: In this Notice of Inquiry (NOI), the Federal 
Energy Regulatory Commission (Commission) seeks comment on whether and 
how the required use of dynamic line ratings (DLR) \1\ is needed to 
ensure just and reasonable wholesale rates. The Commission further 
seeks comment on: Whether the lack of DLR requirements renders current 
wholesale rates \2\ unjust and unreasonable; potential criteria for DLR 
requirements; the benefits, costs, and challenges of implementing DLRs; 
the nature of potential DLR requirements; and potential timeframes for 
implementing DLR requirements.
---------------------------------------------------------------------------

    \1\ A DLR is a transmission line rating that: ``(1) applies to a 
time period of not greater than one hour; and (2) reflects up-to-
date forecasts of inputs such as (but not limited to) ambient air 
temperature, wind, solar heating intensity, transmission line 
tension, or transmission line sag.'' Managing Transmission Line 
Ratings, Order No. 881, Federal Register, 87 FR 2244 (Jan. 13, 
2022), 177 FERC ] 61,179, at P 7 (2021).
    \2\ Consistent with Order No. 881, by ``wholesale rates,'' we 
refer to both rates for the transmission of electric energy in 
interstate commerce and rates for the sale of electric energy at 
wholesale in interstate commerce. Id. P 29.
---------------------------------------------------------------------------

I. Background

    1. On December 16, 2021, the Commission issued Order No. 881 in 
Docket No. RM20-16-000. In that order, pursuant to section 206 of the 
Federal Power Act (FPA), the Commission revised the Commission's pro 
forma open access transmission tariff (OATT) and the Commission's 
regulations to improve the accuracy and transparency of electric 
transmission line ratings.\3\ Specifically, the Commission found that 
the use of only seasonal and static temperature assumptions in 
developing transmission line ratings would result in transmission line 
ratings that do not accurately represent the transfer capability of the 
transmission system.\4\ The Commission found that inaccurate 
transmission line ratings result in unjust and unreasonable Commission-
jurisdictional rates.\5\
---------------------------------------------------------------------------

    \3\ Id. P 1.
    \4\ Id. P 3.
    \5\ Id.
---------------------------------------------------------------------------

    2. Accordingly, the Commission required, among other things and 
with limited exceptions: (1) Transmission providers \6\ to use ambient-
adjusted ratings (AARs) \7\ as the basis for evaluation of transmission 
service requests that will end within 10 days of the request and as the 
basis for their determination of the necessity of certain curtailment, 
interruption, or redispatch of transmission service anticipated to 
occur within those 10 days; (2) transmission providers to use seasonal 
line ratings as the basis for evaluation of transmission service 
requests ending more than 10 days from the date of the request and as 
the basis for the determination of the necessity of curtailment, 
interruption, or redispatch of transmission service that is anticipated 
to occur more than 10 days in the future; and (3) regional transmission 
organizations and independent system operators (RTOs/ISOs) to establish 
and maintain the systems and procedures necessary to allow transmission 
owners in their regions to electronically update transmission line 
ratings on at least an hourly basis (thereby enabling the RTO/ISO to 
use DLRs from transmission owners that voluntarily adopt them).\8\
---------------------------------------------------------------------------

    \6\ Consistent with Order No. 881, we use transmission provider 
to mean any public utility that owns, operates, or controls 
facilities used for the transmission of electric energy in 
interstate commerce. 18 CFR 37.3 (2021). Therefore, unless otherwise 
noted, ``transmission provider'' refers only to public utility 
transmission providers. Furthermore, the term ``public utility'' as 
found in section 201(e) of the FPA means ``any person who owns or 
operates facilities subject to the jurisdiction of the Commission 
under this subchapter.'' 16 U.S.C. 824(e).
    \7\ An AAR is a transmission line rating that: ``(1) applies to 
a time period of not greater than one hour; (2) reflects an up-to-
date forecast of ambient air temperature across the time period to 
which the rating applies; (3) reflects the absence of solar heating 
during nighttime periods where the local sunrise/sunset times used 
to determine daytime and nighttime periods are updated at least 
monthly, if not more frequently; and (4) is calculated at least each 
hour, if not more frequently.'' Order No. 881, 177 FERC ] 61,179 at 
P 4.
    \8\ Id. PP 4-9.
---------------------------------------------------------------------------

    3. While acknowledging in Order No. 881 that, in certain 
situations, using transmission line ratings that are based on factors 
beyond forecasted ambient air temperatures and the presence or absence 
of solar heating--such as DLRs--may lead to greater accuracy of 
transmission line ratings, the Commission declined to mandate DLR 
implementation based on the record in that proceeding.\9\ Instead, the 
Commission incorporated that record on DLRs into the instant 
proceeding, Docket No. AD22-5-000, which the Commission opened to 
further explore DLR implementation.
---------------------------------------------------------------------------

    \9\ Id. PP 7-8, 36, 252.
---------------------------------------------------------------------------

    4. The Commission explained that, unlike AARs, DLRs are based not 
only on forecasted ambient air temperatures and the presence or absence 
of solar heating, but also on other weather conditions, such as wind, 
cloud cover, solar heating intensity (instead of only daytime/nighttime 
distinctions used in AARs), and precipitation, and/or on transmission 
line conditions such as tension or sag.\10\ The Commission agreed with 
commenters that highlighted the benefits to DLR implementation.\11\ For 
example, the Commission agreed with the Exelon Corporation (Exelon) 
that there may be applications in which DLRs can provide net benefits 
to customers, such as when the limiting element for a transmission 
facility experiencing significant congestion is the conductor and 
conditions besides ambient air temperature have a consistent and 
significant impact on the power carrying capabilities of the line. The 
Commission also acknowledged that the use of DLRs generally allows for 
greater power flows than would otherwise be allowed and that their use 
can also detect situations where power flows should be reduced to 
maintain safe and reliable operation and avoid unnecessary wear on 
transmission equipment.\12\
---------------------------------------------------------------------------

    \10\ Id. P 7.
    \11\ Id. P 253.
    \12\ Id.
---------------------------------------------------------------------------

    5. Despite the benefits of DLR implementation, the Commission 
recognized that DLR implementation also presents additional costs and 
challenges not found in AAR implementation, such as costs associated 
with placement of sensors, cybersecurity, and other costs.\13\ The 
Commission found that the record in the Order No. 881 proceeding, 
Docket No. RM20-16-000, was not sufficient for it to evaluate the 
relative benefits and costs and challenges of DLR implementation.\14\
---------------------------------------------------------------------------

    \13\ Id. P 254.
    \14\ Id.
---------------------------------------------------------------------------

II. Discussion

    6. We are issuing this NOI to further explore whether DLR 
implementation is required to ensure just and reasonable wholesale 
rates. We invite all interested persons to submit comments and reply 
comments on any or all of the questions listed. Commenters need not 
answer all the questions. Commenters should organize responses 
consistent with the structure of the attached questions.

[[Page 10351]]

Commenters are also invited to reference material previously filed, 
including in Docket Nos. RM20-16-000 and AD19-15-000, but are 
encouraged to avoid repetition or replication of previous material. 
Initial comments must be submitted on or before 60 days after the date 
of publication of this NOI in the Federal Register. Reply comments must 
be submitted on or before 90 days after the date of publication of this 
NOI in the Federal Register.

A. Questions on the Need for DLR Requirements

    7. In Order No. 881, the Commission found that transmission line 
ratings directly affect wholesale rates because transmission line 
ratings and wholesale rates are inextricably linked.\15\ It explained 
that transmission line ratings represent the maximum transfer 
capability on a transmission line, which, in turn, determines the 
quantity of energy that can be transmitted from suppliers to load. The 
Commission explained that, all else equal, as transfer capability 
declines, wholesale rates increase. The Commission also observed that 
inaccurate transmission line ratings can result in underutilization (or 
overutilization) of existing transmission facilities, thereby sending a 
signal that there is less (or more) transfer capability than is truly 
available.\16\
---------------------------------------------------------------------------

    \15\ Id. P 30.
    \16\ Id. PP 30, 34.
---------------------------------------------------------------------------

    (Q1) As a threshold matter, even for transmission lines that 
incorporate AARs, is there a need to further increase the accuracy 
of transmission lines ratings through the implementation of DLRs to 
ensure just and reasonable wholesale rates? Why or why not? If yes, 
please explain whether a requirement by the Commission to adopt DLRs 
is needed.
    (Q2) What, if any, barriers to DLR implementation exist today? 
Are potential requirements to implement DLRs necessary to address 
these existing barriers? Why or why not?

B. Questions on Potential Criteria for DLR Requirements

    8. Commenters in the Order No. 881 proceeding expressed a range of 
opinions on whether and how the Commission should require the 
implementation of DLRs. On one end of the spectrum, Southwest Power 
Pool, Inc.'s Market Monitoring Unit (SPP MMU) stated that it supported 
a requirement for DLR implementation on all transmission lines.\17\ 
Similarly, Industrial Customer Organizations and the R Street Institute 
contended that DLRs should be required by default, with exceptions 
given when justified by cost-benefit analyses.\18\ On the other end, 
many commenters, including nearly all transmission owners that filed 
comments about DLRs, either opposed a requirement to implement DLRs on 
all transmission lines \19\ or opposed a DLR requirement in any 
form.\20\
---------------------------------------------------------------------------

    \17\ SPP MMU, Comments, Docket No. RM20-16-000, at 4 (filed Mar. 
22, 2021).
    \18\ R Street Institute, Comments, Docket No. RM20-16-000, at 3 
(filed Mar. 22, 2021); Industrial Customer Organizations, Comments, 
Docket No. RM20-16-000, at 5 (filed Mar. 22, 2021).
    \19\ Arizona Public Service Company, Comments, Docket No. RM20-
16-000, at 8 (filed Mar. 22, 2021); New York Transmission Owners, 
Comments, Docket No. RM20-16-000, at 2 (filed Mar. 22, 2021); 
Indicated PJM Transmission Owners, Comments, Docket No. RM20-16-000, 
at 13 (filed Mar. 22, 2021); Pacific Gas and Electric Company, 
Comments, Docket No. RM20-16-000, at 11-12 (filed Mar. 22, 2021).
    \20\ American Electric Power Service Corporation, Comments, 
Docket No. RM20-16-000, at 6 (filed Mar. 22, 2021); Dominion Energy 
Services Inc., Comments, Docket No. RM20-16-000, at 9 (filed Mar. 
22, 2021); Entergy Services LLC, Comments, Docket No. RM20-16-000, 
at 14 (filed Mar. 22, 2021); Bonneville Power Administration (BPA), 
Comments, Docket No. RM20-16-000, at 6 (filed Mar. 22, 2021); 
Exelon, Comments, Docket No. RM20-16-000, at 3 (filed Mar. 22, 
2021); PacifiCorp, Comments, Docket No. RM20-16-000, at 5-6 (filed 
Mar. 22, 2021); National Rural Electric Cooperative Association and 
the Large Public Power Council, Comments, Docket No. RM20-16-000, at 
3 (filed Mar. 22, 2021); MISO Transmission Owners, Comments, Docket 
No. RM20-16-000, at 45-46 (filed Mar. 22, 2021); ITC Holdings Corp., 
Comments, Docket No. RM20-16-000, at 14-15 (filed Mar. 22, 2021).
---------------------------------------------------------------------------

    9. Other commenters supported targeted or limited DLR 
implementation. For example, the WATT Coalition (WATT) and Clean Energy 
Parties proposed criteria for requiring DLR implementation and 
contended that such criteria could help overcome concern about costs of 
DLRs exceeding benefits.\21\ Specifically, WATT proposed that the 
Commission require ``sensor-based DLRs'' on all thermally limited 
transmission lines rated 69 kV or greater when: (1) Market congestion 
totaling over $1 million has occurred within the past year; (2) the 
transmission line is identified as being a constraint projected to have 
market congestion over $1 million over the coming three years as a part 
of the current RTO/ISO transmission planning cycle process, which can 
be economic or reliability based; (3) thermally limited transmission 
lines show up as limiting in generator interconnection system impact 
studies; or (4) generation curtailed by more than 10% on average for 
one year due to factors that include transmission line capacity.\22\
---------------------------------------------------------------------------

    \21\ WATT, Comments, Docket No. RM20-16-000, at 10-11 (filed 
Mar. 22, 2021); Clean Energy Parties, Comments, Docket No. RM20-16-
000, at 7-10 (filed Mar. 22, 2021); American Clean Power Association 
and the Solar Energy Industries Association (ACPA/SEIA), Comments, 
Docket No. RM20-16-000, at 9-10 (filed Mar. 22, 2021).
    \22\ WATT, Comments, Docket No. RM20-16-000, at 10-11 (filed 
Mar. 22, 2021).

    (Q3) If the Commission were to require DLR implementation, 
should it require the implementation only on certain transmission 
lines, and, if so, what set of criteria should be considered to 
identify transmission lines for DLR implementation? Examples of such 
criteria could include congestion, curtailment levels, voltage 
levels, infrastructure, and/or geography/terrain. Explain why such 
criteria would identify the set of transmission lines on which DLRs 
need to be implemented in order to produce just and reasonable 
wholesale rates.
    (Q4) How should transmission lines be evaluated for whether they 
satisfy such criteria, both initially and going forward? Please 
estimate the number and proportion of transmission lines that would 
likely be implicated by any criteria you recommend.
    (Q5) If the Commission were to require DLR implementation based 
on certain criteria, should the criteria be regularly reevaluated to 
ensure such criteria continue to ensure accurate transmission line 
ratings, and, if so, at what interval(s)? How should such regular 
reevaluations work practically?
    (Q6) If such criteria included the magnitude of congestion on a 
transmission line, what metrics exist that assess the magnitude of 
congestion in both or either RTO/ISO and/or non-RTO/ISO regions? For 
any congestion metrics suggested, what data sources are available?
    (Q7) Implementation of the requirements adopted in Order No. 881 
are expected to change congestion patterns. How should these 
congestion pattern changes be accounted for when considering whether 
a transmission line satisfies the criteria established as part of 
any potential DLR requirements?
    (Q8) What are the differences, if any, between RTOs/ISOs and 
non-RTO/ISO transmission providers that the Commission should 
account for when considering any DLR requirements?
    (Q9) If the Commission were to require DLR implementation based 
on certain criteria, should it require that new transmission lines 
be evaluated to determine whether they must implement DLRs? Are 
there any characteristics of new transmission lines that warrant 
different criteria?
    (Q10) If the Commission were to require DLR implementation, how 
should that requirement be considered in regional transmission 
planning and interconnection processes?
    (Q11) If the Commission were to require DLR implementation based 
on certain criteria, what transparency measures should the 
Commission require? For example, should the Commission consider 
requiring transmission providers to submit informational reports 
that show which transmission lines meet any determined criteria for 
DLR implementation? And/or should the Commission require 
transmission providers to post the same on their Open Access Same-
Time Information System websites?

C. Questions on the Benefits, Costs, and Challenges of Implementing 
DLRs

    10. While the Commission in Order No. 881 highlighted the potential

[[Page 10352]]

benefits of DLR implementation, including potential increases in the 
accuracy of transmission line ratings and potentially greater power 
flows, it recognized that there are costs and challenges associated 
with DLR implementation. Some commenters in the Order No. 881 
proceeding provided DLR cost estimates, but there was limited detail 
around those estimates and those estimates varied. For example, BPA 
asserted that DLR implementation would require investment of 
potentially over $1 million per transmission line in monitoring 
equipment, software, and hardware to submit and host the data.\23\ MISO 
Transmission Owners contended that DLR implementation could cost 
between $100,000 and $200,000 per transmission line, and thus the 
overall cost to implement DLRs for all transmission lines in MISO would 
be approximately $1.5 billion.\24\ SPP estimated that DLR 
implementation that requires an energy management system (EMS) upgrade 
would cost transmission owners up to $1 million and, without upgrading 
the EMS, DLR implementation would cost an additional $100,000 to 
$500,000 annually in additional supervisory control and data 
acquisition (SCADA) communications with the reliability coordinator's 
EMS.\25\
---------------------------------------------------------------------------

    \23\ BPA, Comments, Docket No. RM20-16-000, at 6 (filed Mar. 22, 
2021).
    \24\ MISO Transmission Owners, Comments, Docket No. RM20-16-000, 
at 47 (filed Mar. 22, 2021) (deriving $1.5 billion by estimating 
$150,000 per line multiplied by 10,000 lines on the MISO system).
    \25\ SPP, Comments, Docket No. RM20-16-000, at 12 (filed Mar. 
22, 2021).

    (Q12) For any DLR requirement criteria you identified in 
response to question Q3 above, please explain and, if possible, 
quantify the potential annual gross market benefits that would be 
expected to result from such a requirement.
    (a) If possible, please also provide estimated upper and lower 
bounds on such gross market benefit estimations based on favorable 
and unfavorable assumptions.
    (b) How might these benefits change with geography/terrain, 
communication infrastructure, and transmission path?
    (c) To what extent might DLR implementation shift congestion to 
new areas? How would these shifts in congestions patterns affect the 
overall benefits of DLR implementation?
    (d) Please describe the method and assumptions used to estimate 
gross market benefits.
    (Q13) If you have experience implementing (or evaluating the 
implementation of) DLRs, please describe your experience and, if 
applicable, explain your specific DLR design, installation, and 
operating decisions, choice of facilities on which to implement 
DLRs, the implications for reliability, and how such DLR 
implementation affected transmission transfer capability.
    (Q14) What are the expected costs and challenges of implementing 
DLRs (separate from the costs associated with Order No. 881 
implementation)?
    (a) How are these costs and challenges divided between initial 
implementation (e.g., sensor purchase and installation, EMS 
upgrades, and communications upgrades) and ongoing operations and 
maintenance (e.g., sensor maintenance, communications maintenance, 
and forecasting)?
    (b) How might these costs and challenges change with geography/
terrain, communication infrastructure, and transmission path?
    (c) Are there any published reports or studies assessing the 
costs, benefits and challenges of DLR implementation? If so, please 
identify and briefly describe these studies.
    (d) Please identify any factors or situations that might cause 
DLR implementation to be prohibitively expensive, and please 
describe alternative implementation approaches that could limit 
those costs.
    (e) Please describe any advantages or disadvantages related to 
costs and challenges to implementing DLRs concurrently with the 
requirements of Order No. 881 (as opposed to after Order No. 881 is 
implemented). For example, are the EMS and communication upgrades 
required to implement AARs sufficient to support the use of DLRs?
    (Q15) Please describe the cybersecurity challenges of DLR 
implementation. What are the potential impacts to reliable 
operations if the digital devices that monitor or communicate line 
conditions used for establishing DLRs are manipulated or rendered 
inoperable by a cyber event? What relevant procedural or technical 
cybersecurity controls exist that would mitigate such risk?
    (Q16) If the Commission were to require DLR implementation, 
should the Commission direct NERC to evaluate how this requirement 
could introduce new risks to the reliable operation of the BES and 
whether any standards require modification to address any risks?

D. Questions on the Nature of Potential DLR Requirements

    11. DLRs are generally based on a combination of real-time measured 
data and various forecasts that are used to compute up-to-date 
transmission line ratings. The real-time measured data is typically 
gathered using field located sensors.
    12. In their comments in the Order No. 881 proceeding, WATT 
suggested a requirement that transmission providers implement ``sensor-
based DLRs'' in certain circumstances (i.e., a requirement that 
transmission line ratings incorporate real-time data from field-based 
sensors on weather and/or transmission line parameters, such as sag, 
tension or temperature).\26\ Alternatively, transmission line ratings 
could be based on up-to-date forecasts of additional weather input and/
or transmission line parameter values.
---------------------------------------------------------------------------

    \26\ WATT, Comment, Docket No. RM20-16-000, at 10-11 (filed Mar. 
22, 2021); ACPA/SEIA, Comments, Docket No. RM20-16-000, at 9-10 
(filed Mar. 22, 2021).
---------------------------------------------------------------------------

    13. The following questions seek information regarding potential 
approaches for a DLR requirement.

    (Q17) If the Commission required DLRs in some circumstances, 
would it be appropriate to require transmission providers to 
calculate transmission line ratings based on up-to-date forecasts of 
additional weather factors beyond those required in Order No. 881? 
Why or why not? If so, please explain what additional factors (e.g., 
wind speed, wind direction, solar irradiance (beyond day/night)) 
should be considered in transmission line rating calculations.
    (Q18) To what extent would it be appropriate to rely on sensor-
based measurements of line parameters \27\ such as line sag, line 
tension, or conductor temperature in calculating line ratings, 
either in addition to, or in lieu of, forecasted weather factors 
described in Q17? In what circumstances should DLR approaches 
augment any sensor-based measurements of transmission line 
parameters with weather forecasts (e.g., from the National Oceanic 
and Atmospheric Administration or another weather service)? To what 
extent are sensor-based measurements of line parameters useful in 
determining longer-term forecasted line ratings (e.g., 2-7 days 
ahead), rather than just instantaneous or very short-term 
calculations of line ratings? How does the ability to forecast line 
ratings compare between DLR approaches that rely primarily upon 
sensor-based measurements of transmission line parameters and those 
that rely upon weather data?
---------------------------------------------------------------------------

    \27\ See, e.g., LineVision, Comments, Docket No. RM20-16-000, at 
2-3 (filed Mar. 22, 2021).
---------------------------------------------------------------------------

    (Q19) Should the Commission consider sensor-based DLR 
requirements, such as those suggested by WATT? If yes, what level of 
sensor coverage and performance requirements for such sensors should 
be required? Please explain whether the Commission would need to 
specify details like the types of sensors, how many are installed, 
what they measure, and the quality of their data? Would a sensor-
focused requirement that specifies the types of technologies 
potentially become stale as DLR technologies evolve? Why or why not?
    (Q20) In Order No. 881, the Commission adopted exceptions from 
the AAR requirements to ensure the safety and reliability of the 
transmission system and for transmission lines with transmission 
line ratings that are not affected by ambient air temperature or 
solar heating.\28\ Please explain whether the Commission should 
adopt the same or similar exceptions for DLR requirements. Are there 
any different/other exceptions from the application of DLR

[[Page 10353]]

requirements that the Commission should consider? If so, what are 
these exceptions?
---------------------------------------------------------------------------

    \28\ Order No. 881, 177 FERC ] 61,179 at PP 227-228.
---------------------------------------------------------------------------

    (Q21) In Order No. 881, the Commission established requirements 
for AARs to be applied to a period not greater than one hour and for 
AARs to be updated hourly.\29\ Is this time resolution and 
calculation frequency also appropriate for DLR requirements or 
should an alternative approach be considered? Why?
---------------------------------------------------------------------------

    \29\ Id. PP 162, 168. See also Pro Forma OATT attach. M, AAR 
Definition.
---------------------------------------------------------------------------

    (Q22) How might the Commission consider potential requirements 
for DLR implementation on transmission lines that are on the seam of 
multiple transmission provider service territories? What additional 
coordination between neighboring transmission owners and 
transmission providers, if any, might be necessary?
    (Q23) In Order No. 881, the Commission required AARs to be used 
for near-term transmission service, defined as transmission service 
that ends not more than 10 days after the transmission service 
request date (i.e., within the next 10 days).\30\
---------------------------------------------------------------------------

    \30\ Order No. 881, 177 FERC ] 61,179 at P 86.
---------------------------------------------------------------------------

    (a) Within what timeframes should the Commission require 
transmission providers to calculate transmission line ratings \31\ 
using DLRs (on transmission lines for which DLRs are required)? Does 
this depend on which DLR approach (weather-based or line parameter-
based) is used for a particular DLR implementation?
---------------------------------------------------------------------------

    \31\ We clarify that we use the phrasing ``require transmission 
providers to calculate'' consistent with Order No. 881, in which the 
Commission clarified ``that hourly (or more frequent) querying of 
`look-up tables' or similar pre-calculated AAR databases will 
satisfy the requirement that AARs be calculated at least each 
hour.'' Id. PP 141-142.
---------------------------------------------------------------------------

    (b) For which transmission services (e.g., hourly point-to-point 
transmission service, daily point-to-point transmission service, 
weekly point-to-point transmission service, etc.) should the 
Commission require the use of DLRs?
    (c) What data on the accuracy of forecasting wind speed, wind 
direction, and/or other DLR variables would support the DLR 
implementation timeframes and transmission services you recommend 
above in (a) and (b)?
    (Q24) If the Commission were to decide that a requirement to 
implement DLR is appropriate:
    (a) Should the Commission limit the number or proportion of 
transmission elements that a transmission provider must implement 
DLRs on at any one time, even if such elements otherwise met the 
criteria for a DLR requirement? If so, should such a limit be based 
on a number or percentage of transmission elements, and if so, what 
number or percentage?
    (b) Should the relevant transmission element for such a limit be 
considered individual transmission lines, or individual transmission 
line-miles, or some other unit? Or, if such a limit is necessary, 
would some other approach be better? Explain why you recommend any 
particular approach.
    (c) Should such a limit be applied each time a transmission 
provider is required to evaluate whether DLRs need to be implemented 
on additional transmission lines (as contemplated below in Q29)?
    (Q25) If changed circumstances result in a transmission line no 
longer meeting the DLR criteria, should the transmission provider 
continue to be required to use the DLR to calculate the rating for 
that line? Please explain why or why not.

E. Questions on Potential Timeframes for Implementing DLR Requirements

    14. In Order No. 881, the Commission required AARs to be 
implemented no later than three years from the compliance filing due 
date.\32\ The Commission explained that three years was consistent with 
the implementation schedule most commonly suggested by transmission 
owners for AAR implementation on priority transmission lines and that 
three years would be sufficient time for transmission owners and 
transmission providers to implement changes to their processes and 
systems to comply with the requirements adopted in the final rule.
---------------------------------------------------------------------------

    \32\ Id. P 361.

    (Q26) What would be the appropriate amount of time, either from 
your experience or by your estimation, necessary for each of the 
following DLR implementation steps identified below?
    (a) Transmission line identification for DLR system application.
    (b) DLR System design.
    i. Field sensors and/or monitoring equipment design including 
specification, procurement, and installation.
    ii. Communication infrastructure design, including 
specification, procurement, and installation.
    iii. Process coordination between DLR field data and EMS, 
including any line rating database upgrades or necessary 
modifications.
    iv. DLR system integration and testing.
    (c) Any other steps needed to implement DLR system.
    (Q27) Can any of the steps identified in Q26, be completed 
concurrently such that the total estimated DLR installation time 
might be faster than the sum of each step? If so, which steps can be 
completed concurrently? How might the implementation of Order No. 
881 affect the time needed to implement DLR?
    (Q28) If, after the initial implementation of DLRs, the 
transmission provider identifies additional transmission lines that 
meet the DLR criteria, how long would it take to implement DLRs on 
those additional transmission lines?
    (Q29) If the Commission required DLRs in certain situations 
based on transmission line criteria, how frequently should 
transmission owners consider whether additional lines might meet the 
criteria for DLR implementation? That is, should the Commission 
require a periodic restudy of transmission systems to determine if 
additional transmission lines meet the criteria for DLR 
implementation? Please explain why or why not. If, during a periodic 
restudy, the transmission provider determines that additional lines 
meet the criteria for DLR implementation, when should the Commission 
require the transmission provider to implement DLRs on those 
additional lines?

III. Comment Procedures

    15. The Commission invites interested persons to submit comments on 
the matters and issues proposed in this NOI, including any related 
matters or alternative proposals that commenters may wish to discuss. 
Comments are due April 25, 2022 and Reply Comments are due May 25, 
2022. Comments must refer to Docket No. AD22-5-000 and must include the 
commenter's name, the organization they represent, if applicable, and 
their address.
    16. 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 should be filed in native applications or print-to-PDF format 
and not in a scanned or picture format. Commenters filing 
electronically do not need to make a paper filing.
    17. Those unable to file electronically may mail comments via the 
U.S. Postal Service to: Federal Energy Regulatory Commission, Secretary 
of the Commission, 888 First Street NE, Washington, DC 20426. Hand-
delivered comments or comments sent via any other carrier should be 
delivered to: Federal Energy Regulatory Commission, 12225 Wilkins 
Avenue, Rockville, MD 20852.
    18. 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.

IV. Document Availability

    19. 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). At 
this time, the Commission has suspended access to the Commission's 
Public Reference Room due to the President's March 13, 2020 
proclamation declaring a National Emergency concerning the Novel 
Coronavirus Disease (COVID-19).
    20. From the Commission's Home Page on the internet, this 
information is

[[Page 10354]]

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.
    21. User assistance is available for eLibrary and the Commission's 
website during normal business hours from the Commission's 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: February 17, 2022.
Debbie-Anne A. Reese,
Deputy Secretary.
[FR Doc. 2022-03911 Filed 2-23-22; 8:45 am]
BILLING CODE 6717-01-P