NERC Continues Focus on Large Load Interconnections

Expanding its efforts to assess and address risks to the bulk power system ("BPS")[1], the North American Electric Reliability Corporation ("NERC") issued an Industry Recommendation on September 9, 2025 ("Large Load IR"), designed to "address the risks observed from the analyzed Large Load[2] behavior and to assess the status of industry preparedness in relation to large loads."[3]

NERC, along with regional and registered entities, have been studying BPS disturbances that have led to customer-initiated, Large Load reductions. To better understand the impact of Large Load penetration on the BPS, NERC:

• Created a Large Loads Task Force ("LLTF") in 2023.
• Published a white paper in 2025 highlighting the characteristics of Large Load, such as rapid fluctuations in demand.

According to NERC, rapid and major swings in Large Loads can impact the "BPS's ability to maintain frequency, regulate transmission voltage, and otherwise maintain stability."[4]

Recommendations

The Large Load IR outlines the following recommendations for functional groups of registered entities, including Transmission Owners ("TOs") and Distribution Providers ("DPs"), to help mitigate risks to BPS reliability resulting from Large Load integration:

• TOs should establish clear facility design and performance criteria in their interconnection requirements for Large Loads to mitigate the reliability risk posed by their expected behavior during normal operations and in response to system disturbances.[5]
• Transmission Planners ("TPs") and Planning Coordinators ("PCs") should establish a comprehensive interconnection and system-wide study process using steady-state, dynamic, and short-circuit models to assess reliability impacts of Large Loads.[6]
• TOs should enhance their load commissioning activities to establish a comprehensive commissioning process that ensures operational readiness for Large Loads.[7]
• TOs should establish operating protocols and the necessary communication infrastructure to support reliable ongoing operations after Large Load facilities enter into commercial operation.[8]
• TPs, Resource Planners ("RPs"), and PCs should, in consultation with their appropriate regulatory bodies, identify and implement a process to include Large Loads into their long-term and near-term transmission planning demand forecasts.[9]

Additionally, NERC directed all registered entities belonging to the TO, DP, TOP, RC, BA, TP, PC, and RP functional groups to answer designated questions set forth in the Large Load IR by January 28, 2026.[10]

Implications

NERC is asking for voluntary implementation of its recommendations while requiring registered entities to provide comprehensive responses early next year to avoid potential sanctions. Registered entities should review and implement NERC's guidance while consulting with counsel and industry experts to ensure submission of accurate and timely responses.

Together with FERC's recent actions on reliability, NERC's recommendations underscore the growing pressure on registered entities to proactively demonstrate preparedness and compliance.

If you have any questions, please contact the authors of this advisory.

*Deiman Flores, energy paralegal, also contributed to this article.