NERC Warns Changing Nature of Grid Could Threaten Long-Term Reliability

To ensure reliability, planners and operators of the electric power system will need to be particularly vigilant about the changing characteristics of the grid, according to the latest Long Term Reliability Assessment from the North American Electric Reliability Corp.

“The bulk power system is undergoing unprecedented change on a scale and at a speed that challenges the ability to foresee and design for its future state,” John Moura, NERC’s director of reliability assessment and performance analysis, said in a statement. “Managing the transformation and proactively preparing for the role that the grid will play is the greatest challenge to reliability over the next 10 years.”

Without careful planning, five trends could negatively impact the ability of the bulk power system to service the energy needs in North America over the next 10 years, the assessment said. Those trends are integration of inverter-based resources, growth in distributed energy resources, generation retirements, flat transmission growth, and increased demand growth.

While most areas in North America are projected to have adequate electricity supply resources to meet demand associated with normal weather, reserves in some areas do not meet resource adequacy criteria, NERC said.

Those areas are the Midcontinent Independent System Operator, California, and Ontario.

MISO is projected to have a 1,300-megawatt shortfall next summer that could continue to grow throughout the 10-year assessment period as coal, nuclear and natural gas generation retire faster than replacement resources are connecting, the assessment said.

California is adding enough new resources and retaining sufficient key generators to alleviate near-term capacity shortages, but variable resource output and changing demand could cause energy shortfalls, ranging from 1 to 10 hours, NERC projected.

Ontario will have a reserve margin shortfall of 1,700 MW beginning in 2025 that will continue to grow throughout the 10-year assessment period because of generation retirements and lengthy planned nuclear maintenance outages.

In addition, extreme weather events, like 2021’s Winter Storm Uri, and recent widespread heat waves in the West will continue to strain electricity resources over major parts of North America, even in areas where traditional resource adequacy criteria are met. In particular, the assessment noted that the U.S. Western Interconnection, Texas, New England and the Southwest Power Pool area are at “elevated risk of shortfall” during extreme weather events.

To ensure continued reliability, NERC recommended that grid planners and regulators should:

  • consider extreme scenarios in their resource planning and be mindful of all-hours energy availability analyses and prioritize the development of reliability standard requirements;
  • increase their focus on the technical needs – including data sharing, models and information protocols – to allow the bulk power system to operate with increased amounts of distributed energy resources, which can improve local resilience at the cost of reduced operator visibility into loads and resource availability;
  • address the reliability needs of interdependent electricity and natural gas infrastructures by enhancing the guidelines for assessing and reducing risks through system and resource planning studies and develop appropriate reliability standards requirements to ensure corrective actions are put in place.

Last month, in its Winter Reliability assessment, NERC warned of insufficient electricity supplies this winter, identifying the Electric Reliability Council of Texas, MISO, SERC-East, Western Electricity Coordinating Council-Alberta, Northeast Power Coordinating Council (NPCC)-Maritimes, and NPCC-New England as the regions most at risk.