According to data from EIA’s most recent Electric Power Monthly, since November 2016, more than 75% of Maine’s electricity generation has come from renewable sources, including hydroelectricity. Natural gas accounted for, on average, 19% of electric generation during the same time period, compared to ten years ago, when natural gas accounted for, on average, almost 50% of Maine’s generation. Between 2007 and 2017, Maine was the only state—of the 11 states that used natural gas as the primary fuel source for power generation—where natural gas no longer had the largest share.
Biomass temporarily surpassed natural gas in November 2016 and December 2016 as the predominant fuel source of Maine’s electricity in those months, generating 16% and 21%, respectively. Since 2017, hydroelectricity has remained Maine’s largest electricity-generating source, with the exception of October 2017 when wind was predominant. Hydroelectricity has averaged 276,281 megawatthours (MWh) per month, or 29% of total electricity generation.
Net electricity generation in Maine has been consistently declining since 2010. In 2017, the net electricity generated in the state was 11.3 gigawatt hours (GWh), compared to 17.0 GWh generated in 2010. The largest decline was in electricity generated by natural gas-fired power plants, which decreased from 8.4 GWh in 2010 to 2.2 GWh in 2017. The share of natural gas-fired generation in total generation has declined from 49% in 2010 to 20% in 2017 and to 14% so far this year.
Maine’s Renewable Portfolio Standards (RPS) require electricity providers to fuel 30% of their electricity generation with renewable resources. In addition to policy initiatives, electricity imports from Canada—notably from Quebec—have been contributing an increasingly larger share to Maine’s total generation, displacing natural gas-fired generation as the primary source. Since 2012, electricity imports from Canada have more than tripled, increasing from 0.8 GWh in 2012 to 2.7 GWh in 2017.
Even though current demand is being met with a combination of renewables, natural gas, and Canadian imports, additional natural gas infrastructure is under consideration to maintain reliability in Maine and New England. Natural gas deliveries have grown in the residential and commercial sectors and declined in power and industrial sectors. Residential and commercial deliveries have increased by 128% and 57%, respectively, since 2010. Industrial and power sector deliveries have decreased by 38% and 45%, respectively, since 2010.
The Federal Energy Regulatory Commission (FERC) is conducting an environmental assessment for TransCanada's Portland Xpress Project. The proposed expansion project would add 0.18 billion cubic feet per day (Bcf/d) of capacity into Maine from Canada. Current pipeline capacity into Maine is estimated at 1.7 Bcf/d.
