Key Grid
and Market Stats

Explore some of ISO New England’s most helpful and popular data about the region’s power system and wholesale electricity markets. Many stats illustrate the significant progress made since the ISO’s inception in developing a regional power system that is more reliable, cost-effective, and environmentally sound.

Read the Regional Electricity Outlook (REO) to learn about New England’s decarbonization journey and how the ISO is working to ensure a reliable power system and competitive wholesale electricity markets that will enable the clean-energy future.

Fast Stats

Here’s a quick look at some key statistics about the region, its high-voltage transmission system, and its wholesale electricity markets. Numbers are rounded.

Electricity Use

  • 7.5 million retail electricity customers; population 15.1 million
  • 114,726 gigawatt-hours (GWh) total annual energy served in 2023 (subject to adjustments)
  • 136,355 GWh all-time highest total annual energy served, set in 2005
  • 28,130 megawatts (MW) all-time summer peak demand, set on August 2, 2006
  • 22,818 MW all-time winter peak demand, set on January 15, 2004
  • 1.8% average annual increase in regional electricity demand forecast through 2033, factoring in forecasts for energy efficiency, behind-the-meter photovoltaics, and electrification of transportation and heating
  • 1.1% average annual increase in summer peak demand forecast through 2033 under typical weather conditions, factoring in forecasts for energy efficiency, behind-the-meter photovoltaics, and electrification of transportation and heating
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Resource Mix

  • Nearly 400 dispatchable generators
  • About 29,700 MW of generating capability
  • 99.3% of the region’s electricity in 2023 was provided by natural gas, nuclear, hydro, imported electricity (mostly hydropower from Eastern Canada), and renewables
  • About 40,000 MW of new generating capacity, proposed to be built, though many projects ultimately withdraw (source: January 2023, ISO Interconnection Request Queue)
  • More than 7,000 MW of generation have retired since 2013 or may retire in the next few years
  • About 3,600 MW of demand capacity resources (DCRs)—including active DCRs, energy efficiency, and other passive DCRs—are registered in New England
  • About 1,500 MW of imported electricity are obligated to be available for the region—mostly hydropower from Eastern Canada
  • About 350,000 distributed solar power installations totaling about 6,500 MW (nameplate), with most connected “behind the meter”
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  • 9,000 miles of high-voltage transmission lines (115 kV and above)
  • 13 transmission interconnections to electricity systems in New York and Eastern Canada
  • 864 project components placed in service across the region since 2002 to fortify the transmission system; 29 planned, proposed, or under construction as of the October 2023 System Plan Project List
  • 13% of region’s energy needs met by imports in 2023
  • 9 elective transmission upgrades proposed to help deliver more than 15,000 MW of clean energy to New England load centers, as of November 2023, according to the ISO Generator Interconnection Queue
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  • Around 550 buyers and sellers in the wholesale electricity marketplace
  • The average real-time price for wholesale power in New England in 2023 was $35.70 per megawatt-hour
  • $6.3 billion traded in wholesale electricity markets in 2023: $4.8 billion in energy markets and $1.5 billion in capacity and ancillary services markets
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Air Emissions

  • 98%, 79%, and 37% decrease in annual regional emissions between 2001 and 2022 for sulfur dioxide (SO2), nitrogen oxides (NOX), and carbon dioxide (CO2), respectively
  • 0.5% of the electricity produced in New England came from oil- or coal-fired resources in 2023, compared to 40% in 2000
  • 39% of the electricity produced in New England in 2023 came from resources that do not emit carbon dioxide
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