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 more about how our traditional power grid is evolving and how the ISO is working to solve operational and market challenges that emerge during this major transformation.

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
  • 123,307 gigawatt-hours (GWh) total annual energy served in 2018 (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
  • -0.9% average annual growth in regional electricity demand forecasted through 2027, after factoring in energy efficiency (EE) and distributed generation (DG)
  • -0.04% average annual growth in summer peak demand forecasted through 2027 under normal weather conditions after subtracting EE and DG; -0.2% under extreme summer weather
  • -0.7% average annual growth in winter peak demand forecasted through 2027 under both normal and extreme weather conditions after subtracting EE and DG
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Resource Mix

  • 350 dispatchable generators
  • About 31,000 MW of generating capability for summer and 33,000 MW for winter (seasonal claimed capability)
  • About 48% of the region’s electric generating capacity uses natural gas as its primary fuel (roughly 15,000 MW), with 11% more listing it as a secondary fuel
  • About 20,600 MW of new generating capacity, mostly wind, proposed to be built, though many projects ultimately withdraw (source: January 2019, ISO Interconnection Queue)
  • 5,200 MW of non-gas-fired generating capacity retired or retiring 2013–2021, with over 5,000 MW from coal- and oil-fired plants at risk of retirement in the coming years
  • Over 3,000 MW of active demand response (DR) and energy efficiency and other passive demand resources are registered in New England (February 2019 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—most from Canadian hydropower
  • Over 150,000 solar power installations totaling about 2,900 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
  • 787 project components placed in service across the region since 2002 to fortify the transmission system; 82 planned, proposed, or under construction, as of the October 2018 Regional System Plan Project List
  • 17% of region’s energy needs met by imports in 2018
  • 17 Elective Transmission Upgrades (ETUs) proposed as of the January 2019, ISO Generator Interconnection Queue, totaling nearly 14,000 MW of potential transfer capability, which would help access non-carbon-emitting resources
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  • More than 500 buyers and sellers in the wholesale electricity marketplace
  • About 70% of real-time pricing set by marginal natural-gas-fired generators in the first three quarters of 2017, with wind setting price next most often (15%)
  • $6.9 billion traded in wholesale electricity markets in 2017 (data subject to adjustments): $4.5 billion in energy markets (which had the second-lowest average prices since 2003) and $2.4 billion in capacity and ancillary services markets
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Air Emissions

  • 98%, 74%, and 34% decrease in annual regional emissions between 2001 and 2017 for sulfur dioxide (SO2), nitrogen oxides (NOX), and carbon dioxide (CO2), respectively
  • 34% decrease in coal-fired generation, between 2016 and 2017
  • 16% decline in oil-fired generation from 2016 to 2017
  • 31% increase in production from solar and wind resources, combined, between 2016 and 2017
  • 15% increase in hydroelectric generation
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