WATT Coalition responds to DLR Notice of Inquiry with ACP, SEIA and AEE

Today, the WATT Coalition filed comments in response to the Federal Energy Regulatory Commission’s Notice of Inquiry about the implementation of dynamic line ratings. The American Clean Power Association (ACP), Advanced Energy Economy (AEE) and the Solar Energy Industries Association (SEIA) collaborated on the response.

Read the introduction to the comments below, and download the full comments here.

With Order No. 881, the Federal Energy Regulatory Commission created a new paradigm for transmission line ratings in the United States. The Clean Energy Entities strongly support the Commission’s continuing work to ensure that line rating methodologies support just and reasonable rates. The Clean Energy Entities appreciates the Commission’s finding in Order No. 881 that the “use of DLRs generally allow for greater power flows than would otherwise be allowed, and its use can also detect situations where power flows should be reduced to maintain safe and reliable operation and avoid unnecessary wear on transmission equipment.”

The Commission’s requirement that transmission providers use ambient-adjusted ratings (AAR) will significantly increase transmission capacity and prevent customers from bearing unnecessary costs from phantom congestion. However, dynamic line ratings (DLR) can go further to ensure that congestion costs are only incurred with lines that are truly at capacity. DLR will also help interconnect cheaper and cleaner generating resources and allow grid infrastructure to adapt and better serve changing load and generation profiles. Prior comments of Clean Energy Entities in RM20-16-000 have been incorporated into this docket, so we do not restate those positions here. Where appropriate, some values have been updated in the responses below to reflect impacts of Order No. 881 or updated research and modeling.

Clean Energy Entities have previously suggested criteria for the Commission to use when requiring DLR. The intent was to provide a framework to identify lines where DLR would create system benefit, far beyond the cost of the installation, as an initial phase of operational DLR deployment in the U.S. We note that the Independent Market Monitor for PJM and the market monitoring unit in Southwest Power Pool (referenced in FERC’s NOI) support broader deployment of DLR. A statement from the PJM market monitor in the 2021 State of the Market Report is unequivocal:

The MMU recommends that all PJM transmission owners use the same methods to define line ratings and that all PJM transmission owners implement dynamic line ratings (DLR), subject to NERC standards and guidelines, subject to review by NERC, PJM and the MMU, and approval by FERC.

Clean Energy Entities believe that in addition to the contributions of DLR to reduce congestion costs for just and reasonable rates, DLR’s benefits to reliability and the facilitation of new resource interconnection merit greater deployment than our initial criteria would achieve and supports FERC encouraging transmission owners to deploy DLR well beyond the minimum criteria. A similar recommendation was made in 2006 by the U.S. Canada Power System Outage Task Force:

Develop enforceable standards for transmission line ratings. NERC should develop clear, unambiguous requirements for the calculation of transmission line ratings (including dynamic ratings), and require that all lines of 115 kV or higher be re-rated according to these requirements by June 30, 2005

The Commission could take several approaches to facilitate greater deployment of DLR beyond the minimum criteria, including ensuring that jurisdictional transmission providers consider DLR in their transmission planning processes and when determining Network Upgrades necessary to interconnect new generation resources. We note that the Commission’s Notice of Proposed Rulemaking issued April 21, 2022 in RM21-17-000 did propose consideration of DLR in planning. The Commission should also act in this docket on DLR requirements for transmission providers outside of the planning context.

In April 2022, the Department of Energy released Grid Enhancing Technologies: A Case Study on Ratepayer Impact. The study found that using DLR on just 16 transmission line segments would reduce New York’s wholesale electricity cost by $1.8 million per year and reduce the gigawatt hours of renewable generation curtailed in the area by 9% overall. In addition, the report finds that DLR provides proactive asset health monitoring and improves situational awareness, supporting grid reliability.

In our response to Question 3, we suggest criteria that the Commission can use to direct transmission owners to unlock these consumer benefits. The recommendations are updated from the WATT Coalition’s recommendations submitted to the Commission on March 22, 2021, to reflect the impacts of Order No. 881 and to ensure that entities outside of RTOs will also use DLR.

The Clean Energy Entities strongly support FERC’s continued efforts to develop clear and effective policies for the use of DLR to ensure just and reasonable rates.