New England’s independent grid operator expects electricity use to rise in the coming decade as more homes adopt electric heating and more drivers shift away from gasoline. In a report released May 1, ISO New England projected that electricity demand across its region will grow by about 9% over the next 10 years, according to the report described by the Associated Press.
The operator’s latest annual outlook is more conservative than a year earlier, when ISO New England had forecast about 11% growth over the same period. ISO New England said the shift reflects changes in federal government policies affecting climate and energy, though state-level programs aimed at energy efficiency and electrification continue.
ISO New England also said the region’s demand trajectory has been relatively flat in recent years, which it linked to investments in energy efficiency measures. “We’ve had years of relatively flat demand, and that’s thanks to states in the region making real investments in energy efficiency measures. But looking ahead to the future, there is going to be a shift,” said Mary Cate Colapietro, a spokesperson for ISO New England.
Colapietro said the “two big factors that are driving this growth are the electrification of heating and transportation.” She pointed to heat pumps and electric vehicles as technologies that tend to be more efficient than oil or gas-powered heating and traditional combustion cars, while noting that electricity generation in the United States is increasingly coming from cleaner sources such as solar and wind.
The Capacity, Energy, Loads, and Transmission report that ISO New England issues each year is designed to help utilities and policymakers plan infrastructure investments, the story said. ISO New England, which oversees the wholesale electricity market and manages the flow of power across transmission lines, does not own power plants or transmission lines itself, and it updates its modeling assumptions each year to reflect changes in the bulk power system.
This year’s projections incorporated additional demand from large electricity users for the first time, including estimates for data centers. The report also included behind-the-meter battery storage systems for the first time, and it built its forecasts using data on power demand from homes and businesses, electric vehicles, electric heating systems including heat pumps, and “behind the meter” power generation from solar panels.
Efficiency Maine’s Michael Stoddard said ISO New England’s forecast had become more grounded than earlier projections, describing it as “more reasonable” while still arguing for adjustments. Stoddard said he believes ISO New England has been too aggressive in past expectations about the growing number of electric vehicles and heat pumps in the region, but he also said the operator’s estimates of how much electricity heat pumps consume remain too high and that ISO New England should “start to take a harder look” at that part of the equation.
ISO New England said it updated its assumptions this year for heat pumps’ electricity demand and also factored in reduced demand from building weatherization efforts, Colapietro said in an emailed response. She wrote that the CELT report “goes through a variety of additions, revisions and changes each year to reflect the ever-evolving changes of the bulk power system,” and that “each year our forecasters examine a variety of factors” to develop the long-term projections.
The AP reporting also described diverging incentives at the federal and state levels for electrification. The federal Inflation Reduction Act funded tax credits for heat pumps and electric vehicles, but those credits expired at the end of 2025 after the Trump administration took office and shifted federal policy away from electrification and renewable energy toward continued use of fossil fuels.
Meanwhile, Maine continues to pursue state-mandated goals tied to heat pumps and electric vehicles, according to Efficiency Maine and the governor’s office as described in the story. Maine has legally mandated targets of at least 115,000 fully heated households using heat pumps and an additional 130,000 partially heated by 2030, as well as goals for at least 220,000 battery electric and plug-in hybrid vehicles registered by 2030.
The story said Maine offers rebates for residential and commercial heat pumps through Efficiency Maine, supported by multiple funding sources including utility energy-efficiency set-asides, revenue from ISO New England’s forward capacity market auctions, and the Regional Greenhouse Gas Initiative. Efficiency Maine said that sustained funding has helped contractors expand hiring and training to install heat pumps, and the governor’s office said more than 200,000 heat pumps have already been installed across the state.
For electric vehicles, Maine’s rebates are funded through utilities and the ISO New England forward capacity market, and the story said electric vehicle adoption has been slower, with about 9,700 registered in Maine as of 2024, according to the U.S. Department of Energy. Efficiency Maine has issued about 2,000 rebates for electric vehicles over the past five years, Stoddard said.
Utilities and policymakers are now using those forecasts as they refine Maine’s grid plans. Versant spokesperson Judy Long said Maine’s grid has some capacity to absorb growth in electricity use, particularly after the closure of many former mills, but she said planning for higher winter demand from heat pumps requires investments, with Versant and Central Maine Power having submitted updated integrated grid plans to the Public Utilities Commission for review.
The report’s reduced growth estimate may give utilities somewhat more breathing room as they respond to electrification, Long said, pointing to flexibility built into Versant’s planning. Third Way deputy director for electricity Francesca Hsie said electricity bills do not necessarily rise in lockstep with electricity demand, depending on what the electricity supply mix looks like and how much the grid needs to expand, and she said the focus should be on lowest-cost grid upgrades in the near term.