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Reducing emissions

Carbon Free Boston is our initiative to become carbon neutral by 2050 by significantly reducing greenhouse gas emissions that contribute to climate change.

Global warming is causing our climate to change. Recent climate reports show we're heading towards extreme climate changes unless we can act now. Mayor Walsh has pledged to make Boston a carbon-neutral city by 2050. This means that in 30 years, our community can only release as much carbon pollution as our environment can safely absorb.

Carbon Neutrality Program Manager

Email Kat Eshel to learn more about Carbon Free Boston.

Learn about Boston's emissions
Climate Action Plan Update
Get involved

Stay up-to-date through Greenovate Boston.

2019 Climate Action Plan

The 2019 update lays out the climate strategies we will accelerate over the next five years. We want to increase carbon emissions reduction in Boston’s buildings and transportation.

Explore the plan

Becoming carbon neutral

Mayor Walsh has set a goal of making Boston carbon neutral by 2050. Buildings and transportation make up nearly 99 percent of Boston’s carbon emissions. We are putting in place strategies to cut emissions from both these areas:

  • Buildings: We're transitioning to zero-net carbon new construction. We plan to develop carbon targets to improve existing buildings over time.
  • Transportation: We're putting in place Go Boston 2030 and supporting the adoption of zero-emission vehicles.

We will also take steps to make our energy supply cleaner and more resilient. We plan to reduce the environmental impact of consumption by Bostonians.

Carbon Neutrality

Recent climate reports show we’re heading towards more extreme climate change than previously thought. This includes rising sea levels and severe storms and temperatures.

In the face of this challenge, Boston is taking action to stop our contribution to climate change. Between 2005 and 2016, we reduced the amount of carbon pollution we emit each year by 18 percent. Learn more about our emissions.

Mayor Walsh has a vision for reducing our emissions to fight climate change. He has pledged to make Boston a carbon-neutral city by 2050. Carbon neutrality means that in 30 years, our community can only release as much carbon pollution as our environment can safely absorb.

The science is clear: Climate change has given us hotter and more volatile weather; it has amplified the frequency and impact of severe storms; and it has increased the rate of sea level rise. An international panel of scientists just released a new report saying major impacts could hit worldwide as early as 2040. We don’t have to look far for early warning signs. A dumpster floating down the street at Fort Point in January. Blue Line tracks underwater in March. Floodwaters in Christopher Columbus Park, reaching the Rose Kennedy Greenway for the first time. King tides that routinely flood the Harbor Walk. Driftwood on a soccer field at LoPresti Park in East Boston. The hottest and most humid summer in our recorded history — this year. Climate change is very real to Bostonians. (Read the speech)

Mayor Walsh

We are America’s climate champion, with a target date of 2050 for going 100% carbon-neutral.

Mayor Martin J. Walsh, State of the City 2017


By the numbers

In 2017, the Boston community emitted 6.1 million metric tons of greenhouse gases (GHGs). Emissions came from energy use:

  • in buildings and other facilities, and
  • from transportation.

This is an almost 4 percent decrease from 2016. Overall, Boston’s 2017 emissions represent an 21 percent decrease from 2005. This reduction has occurred at the same time that the population and the number of jobs in Boston have increased. The decrease is in large part due to a cleaner electric grid and buildings switching from fuel oil to natural gas.

Image for 2017 community emissions

The City of Boston has set GHG reduction goals of 25 percent below 2005 levels by 2020 and carbon neutrality by 2050.

Read through the inventory report and methodology.


Image for boston celebrates national energy efficiency day by encouraging all residents to participate in renew boston

We're updating our Climate Action Plan


Next step taken toward implementation of Community Choice Aggregation


Mayor Walsh calls on renewable energy developers for multi-city, large-scale projects

Image for boston skyline

Carbon Free Boston project update

Carbon Free Boston launched

Go Boston 2030

Go Boston 2030 is the City's bold vision for our transportation future. This plan will help the City of Boston meet our emissions reduction goals.

Learn about Go Boston 2030