Intro background


Energy is a critical resource that we rely on to go about our daily activities. Unfortunately, much of our energy use and energy supply is currently unsustainable and causes climate change and environmental degradation. Innovations that allow us to use energy more efficiently and switch to cleaner, renewable fuel sources that can be stored will drastically improve the sustainability of our energy systems.

This page addresses community energy use from our homes, offices, and travel. It also addresses municipal energy use, which includes City-owned facilities, schools, and streets, as well as activities like water and wastewater pumping and solid waste pick-up. 

Power plant on edge of a river with two people kayaking

Community Energy Use

Our Data

In 2019, residents and businesses around Cambridge used 1.65 billion kWh of electricity, 73.5 million Therms of natural gas and 3.1 million gallons of fuel oil to power, heat, and cool buildings. 

Energy from different sources is measured in different ways – electricity is measured in kWh, natural gas in therms, oil in gallons. We can convert these different measures into a common measure- million British Thermal Units (MMBTU) -to better understand and compare total energy use.MMBTUMillion British Thermal Units
Energy from different sources is measured in different ways – electricity is measured in kWh, natural gas in therms, oil in gallons. We can convert these different measures into a common measure- million British Thermal Units (MMBTU) -to better understand and compare total energy use.MMBTUMillion British Thermal Units

Community Energy Use

New England Power Grid Energy Supply

Our modern grid is a massive and complex infrastructure network consisting of everything from power plants, transmission lines, and your own electricity meter. Throughout the United States, the grid is broken downs into smaller sections and here in Cambridge we are part of the ISO New England sub-grid. This chart shows the fuels that were used to power the ISO New England grid in 2021. While we can't have direct control over which electrons produced from which fuel comes into our homes, we can support a cleaner and more fuel-efficient grid with how we contract and purchase our electricity. The City offers residents multiple options for supporting clean energy and has made a commitment to use 100% renewable electricity for all municipal operations. 

2021 Electricity Grid Fuel Mix Data

Explore the Environmental Protection Agency Data here!

Turbines at Block Island offshore wind farm

Block Island Offshore Wind Farm, Rhode Island
Credit: Ionna22 / CC BY-SA 4.0

Cambridge Community Electricity Program

The Cambridge Community Electricity Program is a City electricity aggregation program that supports the development of local renewable energy projects. The program also offers the potential for savings compared with Eversource’s Basic Service price (though savings cannot be guaranteed), and it provides a City-vetted alternative to Eversource’s Basic Service and to other electricity offers in the marketplace. 

As of March 2022, Graham and Parks School hosts a 243kW solar system built with the funds collected from Cambridge Community Electricity program participants. Nearly 40,000 Cambridge Eversource customers already participate. The number of residents and businesses choosing 100% Green Plus carbon-free electricity grew by more than 10% from 2020 to 2021.

Cambridge Community Electricity Program

Community Energy Use

Community Electricity 100% Green Accounts

The Community Electricity Aggregation program offers residents two options that help add clean electricity to the New England power grid. The 100% Green option provides the largest environmental benefit and has seen steady growth in participation since the offering began. 
The Community Electricity Program has helped avoid nearly 25.5 million pounds of CO2 from being emitted since the program started. About 80% of this being from the 100%+ Green accounts. Participating in this program is one effective way to help the City achieve its net zero goals.  

Cambridge Community Electricity Program 100% Green Plus Accounts

Learn more about the Cambridge Community Electricity Program 

Municipal Energy Use

Municipal Energy Use by Sector, 2008-2022

Municipal energy use measures the energy use reductions from all municipal operations including heating schools and City-owned facilities, lighting the streets, pumping water, and driving trash trucks to pick up waste.

We look at energy use by sector to determine how much energy is used in each type of operation so that we can identify opportunities for reductions. In Cambridge, like in many other cities, buildings use the majority of our overall energy consumption. The City’s efforts to reduce energy use from all sectors saves money and minimizes our impact on the environment.

Municipal Energy Use

Cambridge Energy Use by Fuel, 2008-2022

This graph shows how the fuels that the City of Cambridge has changed since 2008. We have reduced our consumption of oil by 99%. Oil emits a lot of GHGs when burned, so reducing our consumption of oil has helped to reduce our emissions. 

Different fuels emit different amounts of greenhouse gas emissions. Buring oil releases more carbon than natural gas, so while natural gas consumption has increased emissions have generally trended down as we have reduced our use of oil. The City has also been committed to reducing its consumption of gasoline and diesel fuels, opting instead to electrify the vehicle fleet and using less-harmful fuels such as biodiesel. 

Municipal Energy Use

Purchased Electricity vs Generated Solar Electricity

It's clear that the City purchases far more electricity than it generates, but there has been significant growth over the past few years in the amount of electricity that is being generated on city-owned buildings. 

The City owns 15 different solar arrays throughout municipally owned properties. All these installations work to produce clean electricity that is consumed in our buildings and sent out to the larger grid. Through careful metering we can understand how much electricity these solar panels are producing, in 2022 municipal solar arrays produced around 1.82 million kWh's!

Two people working on rooftop solar panels

Municipal Energy Use

Decreasing Energy Use & Emissions

Between 2008 and 2022, the City reduced its energy use by 20%, but the GHG emissions from energy use went down by 38%.

In addition to reducing energy use, we also switched the kind of energy we use, which reduces emissions from energy even more. For example, several municipal buildings were rebuilt to use less energy, which reduced GHG emissions.  But they also had solar installed on the roof, which produces electricity with zero GHG emissions.

Municipal Energy Use

How is the City Reducing Energy Use?

The City’s efforts to reduce energy use from all sectors save money and minimize our impact on the environment. Efforts include:

  1. Implementing energy efficiency and green building programs.
  2. Installing solar on municipal buildings
  3. Converting streetlights to more efficient LED bulbs.

Solar panels and air ducts on rooftop
LED streetlight

Did You Know?

The City converted 6,578 streetlights to LED bulbs and introduced a remotely controlled, automatic dimming schedule. This reduces the electricity used in street lighting by 80%.

Learn more about the City's streetlight conversion efforts here!

Solar Power Capacity

Total kW of Solar

The publicly and privately-owned solar panels throughout Cambridge generate pollution-free electricity using a source that is in endless supply - the sun. Here we are looking at solar electricity generation capacity, which is the maximum amount of electrical power that could be produced by all of the solar panels in Cambridge under perfect conditions. Solar is growing in Cambridge with close to 900 individual projects and there is still a lot of untapped potential. Cambridge has established a goal to have 55 megawatts of solar by 2030. 

A kilowatt is a measure of power, or how fast something generates or uses energy. The higher a unit’s kW, the faster it uses energy. One kilowatt equals 1,000 watts.kWKilowatt
A kilowatt is a measure of power, or how fast something generates or uses energy. The higher a unit’s kW, the faster it uses energy. One kilowatt equals 1,000 watts.kWKilowatt

Solar Power Capacity

Community-Funded Local Solar

Over 40,000 electricity accounts participate in the Cambridge Community Electricity Program. All the Cambridge Community Electricity Program participants pay a $0.002 charge on each kWh of electricity they use and their collective impact has added over $2 million dollars to our Renewable Energy Fund.  In March 2022, a new 243kW local solar project was installed on Graham and Parks School using Renewable Energy Fund money.  This solar project is collectively “owned” by all the Cambridge Community Electricity Program participants.

 All the RECs from this solar project are retired on behalf of the Community Electricity Program participants, reducing their carbon emissions.  All the solar net metering credits will be sold and the funds re-invested in the Renewable Energy Fund. The result is that each Cambridge Community Electricity Program participant helped to add more renewable electricity to the local electricity grid. The electricity produced by this new solar project will take the place of some fossil fuel-generated electricity.

Graham and Parks School

Graham and Parks School 

Drone image from Tony Akoury 

Solar Power Capacity

Solar on City Buildings

Cambridge has installed a total of 2,520 kW in solar energy capacity across 14 different city owned and operated facilities. These solar panels produce enough power to drive an electric car 7.7 million miles each year! The City has several more projects planned to be constructed over the coming years. While these solar panels provide on-site access to renewable energy the city continues to procure 100% of its electricity from renewable sources.

Muni Solar

Solar Power Capacity

Permits for Solar Installations

The City tracks the number of solar installations going up through electrical and other permit data. Since the late 1990's, the number of installations has grown quite substantially.

 Additionally, if you're thinking about exploring solar for your building but aren't sure where to start check out the solar potential of your building by using this tool

Represents projects that received a permit from Cambridge Inspectional Services. 

Energy Solar Power Capacity

Total kWs of Solar

This graph shows how the total kWs of solar in Cambridge has increased significantly since 1998. There is still a long way to go to reach our short and long term goals.

Person working on solar panels on a rooftop

Did You Know?

As of the end of 2022, there were 888 public and private installations that received permits from the City of Cambridge. All these arrays have close to a combined capacity of 10 MW in electricity.

1 MW of solar energy can power 164 homes!

Check out the solar potential of your home!

How You Can Help

Explore Clean Energy Options

Programs are available for residents and businesses to install solar panels on their homes or offices. If installing solar panels is not an option, you can purchase 100% renewable energy through the Cambridge Community Electricity Program, or invest in community solar!

Purchase 100% renewable energy.
Go solar through Sunny Cambridge.
Support solar without putting panels on your roof!

How You Can Help

Reduce Energy Use in Your Own Home

There are a lot of opportunities to reduce energy use in your own home, such as switching to LED lights, adding insulation, and buying a heat pump. 

Mass Save has a lot of information on energy efficiency.
The City of Cambridge is partnering with BlocPower on a new, one-year pilot to help multifamily buildings complete upgrades that can improve indoor comfort and energy efficiency, while working towards our climate goals.