Stephen George is director, operational performance, training and integration, and Jinye Zhao is technical manager, advanced technology solutions at ISO New England.
Ask any power system operator and they’ll tell you: Early detection is crucial. The sooner we identify a potential problem, the more options operators have at their disposal — allowing issues to be resolved before they become emergencies. This is true whether a challenge develops within a single day, or over a longer-term planning horizon.
ISO New England’s new Probabilistic Energy Adequacy Tool, or PEAT, created as part of a joint effort with the Electric Power Research Institute, is part of our comprehensive and proactive approach to planning for a reliable future power system.
Climate change, and the decarbonization policies states are implementing to curb it, are fundamentally altering the way consumers use electricity in New England, as well as the types of resources that provide that energy. These changing conditions make it more challenging to assess our region’s long-term ability to meet consumer demand.
ISO New England and EPRI recently completed a first-of-its-kind study that analyzed the impacts of extreme weather on the region’s energy supplies within an operational timeframe. The analysis takes into account the increasingly important role weather plays in power system operations, examining how factors such as temperature, cloud cover and wind speed may impact future electric power generation (i.e., energy supplies) and consumer demand.
EPRI reviewed more than 70 years of New England weather data — factoring in several models that forecast how the region’s climate might change — to determine the weather conditions most likely to threaten energy supplies. Then, the team used the ISO’s 21-day assessment tool — itself a one-of-a-kind energy supply outlook — to evaluate the New England power system’s capability to manage disruptions in energy demand and supply over a three-week period under extreme weather conditions.
The study creates a detailed snapshot of risks of energy shortfalls — a condition that happens when the region’s electricity supply falls below consumer demand — for the two target years — 2027 and 2032.
At a high level, we learned that the risk of energy shortfalls during winter cold snaps appears manageable over a 21-day period, meaning that existing situational awareness measures, communication protocols and operating procedures, such as calls for energy conservation, are likely to be sufficient to mitigate the low probability risk of energy shortfalls.
In addition, our results confirm that the region’s energy shortfall risk profile is dynamic and will evolve along with supply and demand patterns. Similarly, we know that an increasingly risky energy profile could emerge if key assumptions about the future system don’t hold.
This fluidity highlights the importance of a key deliverable from the study: development of the PEAT, which acts as an early warning system, identifying circumstances that could lead to an energy shortfall, and alerting the region to the likelihood and magnitude of potential problems. From there, steps can be taken to mitigate the risk.
Beyond its use in this initial study, PEAT provides the region with the framework needed to assess energy adequacy risk moving forward. It will serve as the baseline in discussions with the New England states and other stakeholders on establishing a Regional Energy Shortfall Threshold, meant to indicate an acceptable level of energy shortfall risk common to the six states during extreme weather.
Once the Regional Energy Shortfall Threshold is established, the region can consider potential solutions that would trigger if the PEAT-based energy assessments project risk greater than the agreed-upon threshold. These solutions could include adjustments to wholesale market designs, investments in infrastructure, or dynamic retail pricing and additional responsiveness by end-use consumers. Some of these solutions fall under the purview of the New England states, who will be key participants in the regional discussions about scope, timing and feasibility happening in 2024 and 2025.
Gone are the days when power system planning was simply about making sure there was sufficient steel in the ground on the hottest and coldest days of the year. At ISO New England, we’re building tools that provide vital information about tomorrow’s system, helping us better understand potential risks and how to mitigate them.
By providing trusted information to the region’s energy stakeholders, these tools facilitate our journey to a greener future, and spur the regional conversations and collaboration needed to provide meaningful, long-term solutions to the challenges we’ll meet on the way.
