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.

Learn more about the opportunities and challenges New England faces as the system continues to evolve. Also learn how the ISO is working toward a smarter, greener grid.

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 Learn More

  • 7.1 million retail electricity customers; population 14.7 million
  • 126,955 gigawatt-hours (GWh) total annual energy served in 2015
  • 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
  • Region’s overall electricity demand forecasted to decline -0.2% annually
  • Region’s peak demand under normal weather conditions forecasted to grow 0.2% annually
  • Region’s peak demand under extreme summer weather forecasted to grow 0.3% annually
  • Energy efficiency and distributed generation slows growth in peak demand and flattens overall electricity demand

Resource Mix Learn More

  • 350 generators
  • 31,000 MW of generating capacity
  • 11,500 MW of proposed generating capacity, mostly natural gas and wind (source: August 2016 ISO Interconnection Queue)
  • 4,200 MW of nongas generating capacity retired or retiring 2013–2019, with about 30% of capacity (over 10,000 MW) retiring or at-risk of retirement by 2020
  • 600 MW of active demand response (DR) and 1,900 MW of energy efficiency through the capacity market

Air Emissions Learn More

  • Average emission rates in New England for nitrogen oxides (NOX), sulfur dioxide (SO2), and carbon dioxide (CO2) fell by 66%, 94%, and 26%, respectively, between 2001 and 2014, largely due to changes in the power supply mix

Transmission Learn More

  • 8,600 miles of high-voltage transmission lines (115 kV and above)
  • 13 transmission interconnections to electricity systems in New York and Eastern Canada
  • 16% of region’s energy needs met by imports in 2015
  • 682 project components placed in service across the region since 2002 to fortify the transmission system; 166 planned, proposed, or under construction through 2024 (source: June 2016 Regional System Plan Project List)
  • Developers have proposed multiple transmission projects to access non-carbon-emitting resources

Markets Learn More

  • Over 400 buyers and sellers in the wholesale electricity marketplace
  • $7.2 billion traded in wholesale electricity markets in 2015: $5.9 billion in energy markets and $1.3 billion in capacity and ancillary services markets
  • 75% of real-time pricing set by marginal natural-gas-fired generators in 2015