New England grid prepared for summer demand  

ISO New England, operator of the region’s electric grid, expects sufficient energy supply to meet consumer demand for electricity this summer.  

The ISO predicts electricity demand to reach 24,803 megawatts (MW) under normal weather conditions, and up to 25,886 MW during any periods of above-average summer weather, such as an extended heat wave.  

While the ISO anticipates adequate electricity for homes and businesses this summer, several consecutive days of hot and humid weather, loss of generation, or other factors could cause periods of tight supply margins. ISO New England grid operators have several tools available to manage these stresses and maintain reliability on the system. 

Planning for the summer 

The ISO creates forecasts of available capacity for each summer and winter season, taking into account estimated contributions from all resources, including demand response; unplanned resource outages; imports from neighboring regions; and resource additions and retirements.  

The ISO takes this forecasted available capacity and compares it to expected consumer demand in both normal weather conditions and warmer than normal weather conditions in order to prepare and plan for the increase in electric demand over the summer months.  

Weather is the largest driver of energy use, and the National Oceanic and Atmospheric Administration (NOAA) is predicting warmer than normal temperatures in New England this summer, and precipitation above normal in most of New England, except for northern Maine. 

The results of the ISO’s capacity analyses and energy assessments show the region can expect to have adequate supply to meet consumer demand and required reserves this summer. 

Tools in place to maintain reliability  

ISO New England’s system operators are well-prepared to manage unexpected situations and abnormal conditions that may arise and affect energy demand or supply.  

ISO system operators undergo rigorous training to ensure the reliability of the grid in New England. They participate in 200 hours of continuing education every three years to maintain their certification. This training includes hands-on simulations which prepare them for handling various scenarios during all types of weather conditions. 

System operators have numerous tools to balance load, including increasing production of online generation, dispatching stand-by units, requesting maintenance be deferred, increasing imports, and voluntary reductions of energy use and other energy conserving measures. 

Depending on the severity of the issues, the expected duration of the event and the level of risk to the power system, system operators can use additional tools such as requesting public conservation or implementing controlled power outages. ISO New England does not anticipate public conservation or controlled outages will be needed this summer. 

How the region will meet this summer’s electricity demand 

The ISO expects approximately 29,000 MW of capacity to be available to meet consumer demand for electricity and required reserves, this summer. A variety of resource types make up the resource mix in New England including wind, solar, natural gas, nuclear, hydro, biomass, imports from New York and Canada, and demand response resources that reduce energy usage.  

Behind-the-meter solar photovoltaic installations (BTM PV) are a growing source of energy in the region and predicted to reduce demand by as much as 1,736 MW during the peak hour of demand on days with normal weather conditions this summer. 

Instead of peaking in the mid-afternoon, as was common during summers before widespread solar panel installations, New England grid demand now peaks in the early evening hours. The region has approximately 7,800 MW of BTM PV which effectively pushes the peak hour of grid demand later in the day, when the sun is lower in the sky and production from solar PV systems is reduced. 

Historical patterns 

Last year, consumer demand for electricity peaked July 16 at approximately 24,000 MW—roughly in line with ISO New England’s forecast summer peak under typical weather conditions. The all-time record for regional electricity demand was set on Aug. 2, 2006, when demand reached 28,130 MW after a prolonged heat wave. In New England, consumer demand for electricity is highest during the summer because of air conditioning use.