I’m thrilled to sit down with Christopher Hailstone, a seasoned expert in energy management and renewable energy, who brings a wealth of knowledge on electricity delivery and grid reliability. With his deep insights into the utilities sector, Christopher is the perfect person to help us unpack the latest findings from the North American Electric Reliability Corp’s 2025-2026 Winter Reliability Assessment. In our conversation, we’ll explore the challenges of rising winter demand, the impact of extreme weather on specific regions, the evolving mix of energy resources, and the structural risks facing the bulk power system.
Can you start by walking us through the key findings from NERC’s latest Winter Reliability Assessment for 2025-2026?
Certainly, Silvia. NERC’s report highlights a significant uptick in peak demand for this winter, projecting an increase of about 20 gigawatts compared to last winter. That’s a 2.5% rise, which might not sound huge, but it’s a notable jump when you consider the scale of the bulk power system. On the resource side, though, we’ve only added about 9.4 gigawatts of capacity to meet this demand. While NERC believes all regions should have enough resources for expected peak conditions, the gap between demand growth and resource additions is a red flag, especially if we encounter unexpected challenges like extreme weather.
How does extreme weather factor into NERC’s assessment, and which regions might be most vulnerable?
Extreme weather is a major concern in this report. While resources look sufficient under normal conditions, prolonged or severe cold snaps could push the system to its limits in several areas. For instance, New England might face gas shortages during extended extreme conditions, which could hamper power generation. In the Southeast, high demand scenarios—especially during early morning hours—could strain reserves. Then you’ve got the Electric Reliability Council of Texas area, where strong load growth heightens the risk of supply shortfalls during extreme cold, and the Northwest, where wide-area cold weather could cause thermal plant outages and reduce wind performance. These regions are on notice to prepare for worst-case scenarios.
NERC pointed out a gap between demand growth and resource additions. What’s driving this imbalance?
The imbalance comes down to demand growing much faster than our ability to bring new resources online. We’re seeing steady demand increases—some areas are forecasting nearly 10% growth year-over-year—driven by factors like data center development in places like the U.S. West, Southeast, and Mid-Atlantic. These high-growth regions are putting pressure on reserve margins, signaling a clear need for more capacity. On the flip side, building new resources is a slow process. Supply chain constraints, permitting delays, and the complexity of integrating new types of generation are all bottlenecks. It’s a race to keep up, and right now, demand is winning.
Let’s talk about the changes in the types of resources being added to the system. Can you explain what’s new since last winter?
There’s been a mixed bag of additions to the resource mix. Since last winter, we’ve seen a significant boost in batteries—about 11 gigawatts—and demand response resources, which have increased by 8 gigawatts. These are critical for balancing short-term peaks. Solar capacity is up by 11 gigawatts as well, though it’s only expected to contribute about 1 gigawatt to peak demand due to limited sunlight during winter. Thermal and hydro additions have been modest, totaling just 3 gigawatts. Meanwhile, wind resources are actually contributing 14 gigawatts less this year, largely due to capacity accounting changes in some markets. It shows how the system is evolving, but not all resources are equally effective for winter reliability.
John Moura from NERC mentioned that ‘elevated risk’ is becoming more structural than seasonal. Can you unpack what that means for the power system?
Absolutely. When we talk about structural risk, we’re looking at long-term, systemic challenges rather than just temporary seasonal spikes. Steady demand growth is a big driver—year after year, we’re seeing more load on the system, and it’s not letting up. At the same time, grid operators are grappling with supply chain issues that slow down new resource development, as well as the integration of variable, inverter-based generation like solar and wind. These resources behave differently than traditional thermal plants, and managing them adds complexity, especially during extreme conditions. So, the risk isn’t just a winter problem—it’s baked into how the system is evolving.
What specific recommendations or strategies do you think are most critical for addressing these winter reliability challenges?
NERC’s recommendations are a good starting point, and I’d emphasize a few key actions. First, grid operators need to thoroughly review their seasonal operating plans to anticipate potential stress points. Generation owners must prioritize winter readiness—things like weatherization of equipment to prevent outages during cold snaps. I also think monitoring fuel supplies, especially for gas-fired generators, is critical because the interdependence between gas production and power generation can make or break reliability in harsh conditions. Beyond that, we need broader policy changes to speed up resource additions, like permitting reform and market rules that encourage private investment. It’s about building resilience at every level.
Looking ahead, what’s your forecast for the future of winter reliability in the bulk power system?
I think winter reliability will remain a tightrope walk for the next few years. Demand growth isn’t slowing down, especially with trends like electrification and data center expansion, and we’re still playing catch-up on resources. The shift to more variable generation like solar and wind will continue to challenge grid operators, especially as we retire older, more predictable thermal plants. On the positive side, advancements in battery storage and demand response could help balance the system if we scale them up quickly. But without significant investment in infrastructure and policy support to streamline resource development, we’re likely to see more winters with elevated risk. It’s a solvable problem, but it requires urgency and coordination across the industry.
