Docket Nos. RM22-10, RM22-16 and AD21-13
Item E-2 | News Release 

Item E-2 is a draft Notice of Proposed Rulemaking, issued pursuant to section 215(d)(5) of the Federal Power Act, that proposes to direct the North American Electric Reliability Corporation or “NERC” to develop and submit for Commission approval modifications to Reliability Standard TPL-001-5.1 (Transmission System Planning Performance Requirements) to address transmission system planning for extreme heat or cold weather events that impact the reliable operation of the Bulk-Power System.

This draft proposed rule stems from the Commission’s technical conference on climate change and extreme weather events held on June 1 and June 2, 2021.  Part of the discussion considered ways in which planning practices should evolve to ensure reliable operation of the Bulk-Power System in the face of extreme weather events, which are occurring with greater frequency, and are projected to occur with even greater frequency in the future. 

Since 2011, the country has experienced at least seven major extreme heat and cold weather events, all of which stressed the Bulk-Power System and resulted in some degree of load shed.  In some cases, these events nearly caused system collapse and uncontrolled blackouts, which were only avoided by the actions of system operators.  For example, the extreme weather conditions affecting the southwest region in February 2021 resulted in a cumulative loss of approximately thirty thousand megawatts of generation resources (combining forced outages with scheduled outages), causing the Electric Reliability Council of Texas (ERCOT) to shed load to prevent widespread, uncontrolled blackouts throughout the entire ERCOT Interconnection.

The draft proposed rule focuses on Reliability Standard TPL-001, because this Standard establishes transmission system planning performance requirements to ensure the reliable operation of the Bulk-Power System over a broad spectrum of system conditions and following a wide range of probable contingencies, including extreme events based on operating experience.  However, while TPL-001 references studies for “extreme events,” it does not specifically require performance analysis for extreme heat and cold weather conditions that affect wide geographical areas simultaneously over several days.  In addition, while the standard requires responsible entities (i.e., planning coordinator and transmission planner) to evaluate possible actions to reduce the likelihood or mitigate the consequences of extreme events, these entities are not obligated to develop and implement corrective actions. To address this reliability gap in Bulk-Power System planning, the NOPR proposes to direct NERC to develop modifications to Reliability Standard TPL-001-5.1 to require responsible entities to:

  1. Develop benchmark planning cases based on information such as major prior extreme heat and cold weather events or future meteorological projections;
  2. Plan for extreme heat and cold events using steady state and transient stability analyses expanded to cover a range of extreme weather scenarios including the expected resource mix’s availability during extreme heat and cold weather conditions, and include the broad area impacts of extreme heat and cold weather; and
  3. Develop a corrective action plan that includes mitigation for any instances where performance requirements for extreme heat and cold events are not met.

In addition to extreme heat and cold weather events, the draft proposed rule also seeks comment on whether drought should be included in the scope of Reliability Standard TPL-001 to be modeled in the future to improve system performance during these events.  

Comments in response to the draft proposed rule would be due 60 days following publication in the Federal Register.

This concludes our presentation.  We are happy to take any questions you may have.


This page was last updated on June 16, 2022