NERC warns reliability risk is rising as load growth outpaces infrastructure
Reliability risk across North America is rising over the next decade as electricity demand growth, driven largely by new data centers, outpaces the pace of new generation, transmission and fuel infrastructure needed to support it, the North American Electric Reliability Corporation (NERC) said Thursday in its 2025 Long-Term Reliability Assessment.
NERC said summer peak demand is forecast to grow by 224 gigawatts (GW) over the next 10 years, a more than 69% increase over the demand forecast in last year’s assessment. Winter peak demand is projected to rise even faster, up 246 GW over the same period, as electricity use patterns evolve and more end uses shift toward electric heating and other winter-peaking loads.
“This assessment is not a prediction of failure but an early warning on the trajectory of risk,” John Moura, NERC’s director of Reliability Assessment and Performance Analysis, said during a media briefing Thursday. “The path forward is still manageable but only if planned resources come online and on time.”
NERC’s long-term assessment is built from a mid-2025 “snapshot in time” based on utility and market projections, and it is intended to flag areas where resource adequacy could tighten under the current buildout trajectory. In the briefing, Moura emphasized that the biggest issue is not a lack of awareness, but the speed of change.
“Reliability risk is increasing, and really not because we lack awareness, but that the system is changing faster than the infrastructure need to support it,” Moura said.
Mark Olson, NERC’s manager of Reliability Assessments, said the report’s risk map reflects the highest risk category each assessment area reaches over the next five years, using reserve margin targets and probabilistic analysis to evaluate the likelihood of unserved energy and load loss. Olson said more areas show elevated or high risk as demand projections rise and resource plans become more uncertain.

The report argues that uncertainty is now a structural feature of resource planning, and that timing has become as important as megawatts. NERC said projected retirements remain high, with 105 GW of seasonal peak capacity planned to retire over the next decade, although that total is down 10 GW from the prior assessment.
At the same time, the composition of planned additions is shifting quickly. NERC said battery storage projects have grown to match solar projections, and that natural gas additions represent about 15% of projected capacity additions, followed by wind and hybrid resources at 8% each.
During the call with journalists Thursday, Olson described a key seasonal challenge that planning models are now surfacing more clearly: resources in the development pipeline may show strong capability for summer peaks, but a very different contribution in winter.
“When we look at what their winter capability is, we can see this shortfall emerging where a lot of resource development is going to be needed in order to meet year-round peak demand and pay close attention to those winter demands,” Olson said.
NERC also pointed to lagging transmission development as a constraint on both reliability and resource delivery. The assessment notes that projected transmission development is rising compared with last year, but that miles of projects under construction have not increased substantially yet, and that delays tied to siting, permitting and other process hurdles remain common. Olson said interregional transmission projects are especially important during wide-area weather events because they can support transfers between neighbors.
Moura said the grid’s changing mix is altering what “stress” looks like, and why planning needs to move beyond traditional reserve margin thinking.
“We must move beyond margin only thinking to thinking about probabilistic and energy risk analysis,” he said.
In the briefing, Moura also pointed to system performance concerns that are not captured by an energy-only risk map, including stability challenges during periods of very high inverter-based resource output. He said the industry is paying closer attention to essential reliability services such as inertia, voltage support and frequency response.
“We’ve seen examples of that in the international space, including the recent Iberian Peninsula outage that underscored the need to manage system performance during periods of high inverter-based resource output,” he said.
The assessment’s headline demand story is closely tied to data centers. Olson said new data centers are the main driver of load growth in many areas, though large industrial loads and electrification also contribute.
During the briefing, Moura said flexibility from data centers could help them interconnect faster and reduce the need for near-term system upgrades if their peak contribution can be managed.
“If data centers can offload their demand usage to their backup centers or move load to different data centers … that flexibility, if that can happen and they are committed to not being there on during peak conditions, well, then they can be interconnected a little quicker,” Moura said.
NERC’s recommendations focus on speeding infrastructure development and improving coordination. The organization urged streamlining siting and permitting for generation, transmission and natural gas infrastructure, managing generator deactivations carefully, expanding adequacy assessments that incorporate energy limitations, and improving electric-natural gas coordination as reliance on gas-fired generation increases.
The bottom line, Moura said, is that the trajectory is moving in the wrong direction, but there is still time to bend it.
“The question is no longer whether the change is coming,” he said. “It’s whether the infrastructure and coordination can keep pace.”