MA GHG Emission Trends

Massachusetts greenhouse gas emission trends

Business-As-Usual (BAU) Projections

This graph shows that GHG emissions in Massachusetts decreased by 21% between 1990 and 2016, from approximately 94 million metric tons of carbon dioxide equivalent (MMT CO2e) to less than 75 MMT CO2e.  The graph also shows that the 2016 emissions were significantly less than had been projected in the “Business as Usual  (BAU)” scenario, which was developed  to estimate what emissions in  2010 – 2020 would be without any new policy implementation. The 21% decline in emissions is a result of many factors including changing fuel prices, weather conditions, and implementation of energy efficiency measures and other policies. More information on the 1990 Baseline and BAU Projection for GHG Emissions in Massachusetts can be found at  

The Department of Environmental Protection (MassDEP) estimates the GHG emissions in the Commonwealth using EPA’s State Inventory Tool (SIT), and publishes the Massachusetts Greenhouse Gas Inventory on a regular basis for emissions monitoring and analysis of emission trends. Using the most recent inventory data, the following graphs illustrate GHG emission trends in Massachusetts by sector and by fuel type. Text version of the below graph

MA and US GHG by Sector

In Massachusetts, the transportation sector emits more GHG than other sectors. Nationwide, the transportation and industrial sectors are the largest sources of GHG emissions. Text version of the below graph

MA and US CO2 by Fuel Combusted

Across all sectors, the combustion of petroleum emits more CO2 in Massachusetts and the U.S. than the combustion of other fossil fuels.  Massachusetts has significantly less CO2 emissions from coal use than nationwide. Text version of the below graph

MA CO2 by Fuel Combusted

Total CO2 emissions in Massachusetts are decreasing, largely because natural gas, a cleaner fuel source, is increasingly replacing coal and petroleum in the power sector. The largest demands for petroleum come from the transportation sector, while the largest demand for natural gas comes from heating buildings. Energy efficiency and other policy measures, as well as economic trends and other variables, also influence emission levels. Text version of the below graph

MA Petroleum CO2 by Sector

The electric power sector has seen significant reductions in CO2 emissions from the combustion of petroleum, as many power plants have switched to natural gas as a primary fuel source. Text version of the below graph

MA Coal CO2 by Sector

Since 2008, the electric power sector has also seen significant reductions in CO2 emissions from coal combustion, as that sector has trended toward natural gas as a fuel. Text version of the below graph

MA Natural Gas CO2 by Sector

Between 1990 and 2010, natural gas gained popularity as a cheaper and less carbon intensive fuel source, resulting in higher CO2 emissions from natural gas combustion in the commercial and residential sectors, and especially in the electric power sector. However, since 2010, CO2 emissions from the electric power sector have noticeably decreased due to natural gas being a less carbon-intensive fuel. Text version of the below graph

MA GHG by Sector

Transportation represents the single largest source of the GHG emissions in Massachusetts. Text version of the below graph

MA Electricity GHG by Sector

Electricity consumption in the commercial sector previously emitted more GHG in Massachusetts than electricity consumption by other sectors.  Since 2009, GHG emissions from electricity consumption by the industrial sector have steadily shrunk, while the residential sector has fallen more modestly. Electricity emissions associated with commercial buildings decreased sharply through 2012, but have shown some growth more recently. Text version of the below graph