Like every major American city, Boston runs on fossil fuels. More than 70% of the energy used in the city is in the form of natural gas and fuels refined from oil. Natural gas is the dominant fuel used in to heat space and water in residential, commercial, and industrial buildings, while the bulk of transportation services provided by commercial and private vehicles are powered by gasoline and diesel fuel. The public transportation system operated by the Massachusetts Bay Transit Authority (MBTA) relies on a combination of electricity, diesel fuel, and compressed natural gas.

About 25% of energy use in Boston is electricity from the ISO New England power grid. The types and amounts of energy used to generate that electricity is a major factor in the city’s plan to be carbon neutral by 2050.  Nearly half of the region’s electric generating capacity uses natural gas as its primary fuel, and GHG emissions from that gas combustion are a large entry in the city’s emission inventory.  The two largest low carbon sources of electricity are nuclear energy and hydropower. The region’s two nuclear facilities, Millstone and Seabrook, supply a quarter of the electricity New England consumes in a year. Electricity imported from Canada is generated largely by hydropower. Wind and solar power are growing quickly, but they still represent a small fraction of total generation.