Greenhouse Gas Emissions
Greenhouse gas emissions (GHGs) are produced when we use energy in our homes and offices, dispose of waste or sewage, and use vehicles. GHGs trap heat in the atmosphere, leading to lasting disruptions in our climate, such as higher temperatures, sea level rise, and more frequent extreme weather events that can cause flooding. Cambridge, along with many other cities, organizations, and businesses, both nationally and internationally, has committed to significantly reduce GHG emissions by 2050 to avoid severe impacts from climate change.
Community GHG Emissions
Our Goals
Cambridge has established a goal to have net-zero GHG emissions community-wide by 2050.
The City's greenhouse gas (GHG) emissions inventory for 2012 will serve as a baseline for measuring progress on our emissions reduction goals. The City is currently working on updating the Community GHG inventory which will be available later in 2022.
UNIT | Greenhouse gases (GHGs) have a natural heat trapping capacity which varies by gas. Humans produce more carbon dioxide (CO2) than any other GHG. We count emissions of GHGs based on how each GHG’s heat trapping capacity compares to CO2s. This is called the "CO2 equivalent" (CO2e). We measure GHGs in metric tons of CO2e (MTCO2e). | MTCO2eMetric Tons Carbon Dioxide Equivalent |
| Greenhouse gases (GHGs) have a natural heat trapping capacity which varies by gas. Humans produce more carbon dioxide (CO2) than any other GHG. We count emissions of GHGs based on how each GHG’s heat trapping capacity compares to CO2s. This is called the "CO2 equivalent" (CO2e). We measure GHGs in metric tons of CO2e (MTCO2e). | MTCO2eMetric Tons Carbon Dioxide Equivalent |
Community GHG Emissions
2012 Community GHG Emissions by Sector
As with municipal GHG emissions, buildings are the largest sector of community GHG emissions, with commercial and institutional buildings accounting for more than half of all community emissions. This is followed by residential buildings and then energy industries, which are the generation facilities that provide electricity and heat for the commercial and institutional properties. On-road transportation, which includes all the cars, trucks, and buses that travel on our streets, represents 10.5% of the City’s GHG emissions.
Municipal GHG Emissions
Trends Over Time and Goals
In 2021, the City reduced greenhouse gas emissions (ghg) from municipal operations 38% below 2008 levels. You can see in the graph here that emissions have fluctuated from year to year, but have generally trended downward. The chart also depicts the significant impact of the planned procurement of 100% renewable electricity supply from a new renewable system with a commercial operation date on or about Jan. 2025. You can also see what it will take to achieve the City's 2030, 2040, and 2050 goals.
Cambridge has established a Municipal GHG reduction goal of 30% below 2008 levels by 2020, with a stretch goal of 35%, and Net-Zero by 2050.
How Does Cambridge Track Municipal Emissions?
Cambridge has reduced its GHG emissions by 38% between 2008 and 2021 by decreasing energy use, switching to cleaner fuels, and reducing waste.
Municipal GHG Emissions
2021 Emissions by Sector
We look at GHG emissions by sector to determine the amount of emissions produced by each sector and identify opportunities for reductions. Similar to the energy use profile, the City’s buildings are the largest source of emissions at 68%.
Municipal GHG Emissions
2021 Emissions By Fuel Type
Electricity and natural gas are the two primary fuel types that cause greenhouse gas (GHG) emissions from our municipal operations. This is not surprising given that the buildings sector is our number one emitter.
This pie chart also shows us where there are opportunities to improve. The City has learned a lot about how to be more efficient in our buildings and to integrate renewable energy into our facilities - demonstrated by the 33% reduction that has already been achieved.
Did You Know?
Cambridge's 2021 GHG emissions from municipal operations are equivalent to the GHG emissions from 3,802 passenger vehicles driving for one year.
How You Can Help
Reduce Your Carbon Footprint
Throughout our daily lives, we all take actions that produce GHGs. Here are some actions you can take to reduce your contribution to the community's emissions:
- Reduce your energy use at home or work. Buildings represent nearly two-thirds of community GHG emissions.
- Switch to renewable energy. Clean energy sources produce fewer GHGs than fossil fuels.
- Reduce your waste by recycling and composting. Solid waste and incineration accounts for 6.4% of community GHG emissions.
- Prioritize low-carbon transportation. Cambridge residents have many options to get around without a vehicle.
