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

  • 7.2 million retail electricity customers; population 14.8 million
  • 116,863 gigawatt-hours (GWh) total annual energy served in 2020 (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
  • 1.1% average annual increase in regional electricity demand forecasted through 2030, factoring in forecasts for energy efficiency, behind-the-meter solar photovoltaics, and electrification of electric vehicles and air-source heat pumps
  • 0.1% average annual decrease in summer peak demand forecasted through 2030 under typical weather conditions, factoring in forecasts for energy efficiency, behind-the-meter solar photovoltaics, and electrification of electric vehicles and air-source heat pumps
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Resource Mix

  • 350 dispatchable generators
  • About 31,500 MW of generating capability (seasonal claimed capability)
  • 99.7% of the region’s electricity in 2020 was provided by natural gas, nuclear, imported electricity (mostly hydropower from Eastern Canada), renewables, and other low- or non-carbon-emitting resources
  • About 30,000 MW of new generating capacity, mostly wind, proposed to be built, though many projects ultimately withdraw (source: June 2021, ISO Interconnection Queue)
  • Roughly 7,000 MW of generation have retired since 2013 or will retire in the next few years, with another 5,000 MW from coal- and oil-fired plants at risk of retirement in the coming years
  • About 3,800 MW of active demand response (DR) and energy efficiency and other passive demand resources are registered in New England (August 2021 DRWG monthly statistics)
  • About 1,500 MW in summer and 1,000 MW in winter of imported electricity are obligated to be available for the region—mostly hydropower from Eastern Canada
  • Over 200,000 solar power installations totaling about 4,000 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
  • 834 project components placed in service across the region since 2002 to fortify the transmission system; 59 planned, proposed, or under construction as of the June 2021 System Plan Project List
  • 20% of region’s energy needs met by imports in 2019
  • 14 elective transmission upgrades proposed to help deliver nearly 6,000 MW of clean energy to New England load centers, as of September 2021, according to the ISO Generator Interconnection Queue
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  • More than 500 buyers and sellers in the wholesale electricity marketplace
  • The average real-time price for wholesale power in New England in 2020 was $23.38 per megawatt-hour
  • $5.7 billion traded in wholesale electricity markets in 2020: $3 billion in energy markets (lowest since the start of competitive markets) and $2.7 billion in capacity and ancillary services markets
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Air Emissions

  • 99%, 78%, and 42% decrease in annual regional emissions between 2001 and 2019 for sulfur dioxide (SO2), nitrogen oxides (NOX), and carbon dioxide (CO2), respectively
  • 60% decrease in coal-fired generation, between 2018 and 2019
  • 69% decline in oil-fired generation from 2018 to 2019
  • 13% increase in production from solar and wind resources, combined, between 2018 and 2019
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