Source: U.S. Energy Information Administration, from ISO New England

Republished August 25, 2014 to correct the statement that attributed the proposed construction of new transmission lines to the New England Independent System Operator (ISO-NE). The construction of transmission lines and generation assets falls in the utilities' purview.

Electric operators in New England have been both generating more electricity from natural gas and importing more hydroelectric generation from Quebec over the past decade. These two sources of electricity are displacing the use of coal and oil as generation fuels in New England.

Recent and planned closures of large power plants may cause the independent system operator for New England (ISO-NE) to continue to rely on an increasing amount of hydropower from Quebec. The 745-megawatt (MW) coal- and oil-fueled Salem Harbor Power Station ceased operation on June 1. Pending shutdowns include the 605-MW Vermont Yankee nuclear facility, expected to be shut down at the end of 2014, and the 1,520-MW Brayton Point coal- and natural gas/oil-fired power plant, expected to be shut down in 2017. To make up for the loss of these generators, northeastern utilities and Hydro-Quebec have proposed constructing several transmission lines, including the 1,200-MW Northern Pass, to increase transmission of electricity from Canada. Hydro-Quebec has more than 36,000 MW of installed hydroelectric capacity and has been exporting electricity to New England and New York since the 1980s.

New England states have several reasons to further limit their use of electricity generated from fossil fuels. Constraints on some of the pipelines delivering natural gas into New England have contributed to higher natural gas prices and made electricity relatively more expensive. Also, all New England states have renewable portfolio standards (or in Vermont, a nonbinding goal) requiring that a certain percentage of their electricity comes from renewable sources. Goals and qualifying renewable sources differ by state. For instance, Rhode Island's goal is 16% renewable electricity by 2020 and New Hampshire's is 24.8% by 2025; both states have limits on the size of hydroelectric facilities whose generation qualifies.

Several New England states also have energy efficiency resource standards or goals, which act like renewable portfolio standards, but are for implementing energy efficiency. Energy efficiency is among the reasons for relatively little change in total system demand over the past decade in New England, despite 3% growth in total population from 2004 to 2012.

Finally, New England states are part of the Regional Greenhouse Gas Initiative (RGGI), a market-based regulatory program that places a cap on carbon dioxide emissions from the power sector. The cap is reduced over time, encouraging states to generate more of their electricity using low- or zero-carbon sources.

Principal contributors: Michael Grubert, Bill Booth