If you ask people the major cause of greenhouse gas emissions in our city, most would probably say “traffic.” Wrong! Buildings in Cambridge account for 80 percent of total GHG emissions. And the largest ones account for about 70 percent of those emissions.

In 2014, Cambridge passed the Building Energy Use Disclosure Ordinance. The largest buildings – commercial and institutional ones of more than 25,000 square feet, and residential buildings of 50 units or more – were required to report their emissions annually. About 1,100 large buildings are covered by the law.

The expectation behind the reporting requirement was that it would encourage buildings to cut emissions, but emissions have kept going up. Large commercial and institutional building emissions increased 29 percent in our city between 2012 and 2019. Some large buildings are out of compliance with even reporting their emissions.

Last year, Cambridge’s Net Zero Action Plan Task Force proposed requiring emissions reductions in large buildings. This approach was anticipated in the original Beudo ordinance if reporting by itself did not reduce emissions. This February, the city manager and the Community Development Department proposed amendments that would require large buildings to begin reducing their emissions, reaching net zero by 2050.

The amendments require large buildings to cut emissions by 20 percent over baseline in 2025 to 2029, by 40 percent in 2030 to 2034, by 60 percent in 2035 to 2039 and by 80 percent in 2040 to 2044, with 100 percent reduction by 2050. Labs and affordable housing may begin reducing emissions later, in 2027, but must reach net zero by 2050.

We believe reaching net zero by 2050 is too late for our city, which is why we support an alternative proposal to reach net zero emissions for large buildings by 2035. The alternative proposal, advanced as additional amendments by councillors Patty Nolan and Quinton Zondervan, speeds up the emissions reduction goals with a 20 percent reduction by 2025 and annual targets of 8 percent reductions starting in 2026. In this plan, labs (a rapidly expanding source of emissions in our city) have the same schedule as other commercial and institutional buildings. And as part of a proposed Green New Deal for Cambridge, in the Nolan-Zondervan plan any large commercial building built in 2025 or later must be net zero.

The climate crisis is an emergency that requires our immediate attention – a public health emergency, an equity emergency, an ecological emergency, an existential emergency. From killer heat waves to flooding, the effects of climate change are all too evident, but they are borne disproportionately by communities of color. Vulnerable populations such as children and the elderly are the groups most affected by hotter summers and by the pollutants that are emitted when gas and oil are burned in our neighborhoods.

A 2035 net zero goal for large buildings matches Cambridge’s commitment to 100 percent clean and renewable energy by 2035, a commitment affirmed by the City Council in December.

The emissions reduction goals are pragmatic and feasible. There are accessible strategies that large-building owners can use now to reduce emissions. For example, they can enter into a Power Purchase Agreement for renewable energy and replace oil or gas heat with electrical, solar or geothermal systems. City buildings with green energy systems include the King Open and Cambridge Street Upper School campus and the massive new biotech building on Binney Street. Buildings that need more time can pay an “alternative compliance credit” to offset emissions, but that is intended as a stopgap measure. Shifting to green energy in large buildings will not only protect our health and our environment; it will also create excellent high-paying jobs for our community.

The Beudo amendments are now making their way through the City Council process. We are asking our city councillors to vote in favor of the Nolan-Zondervan Amendments, aiming for net zero by 2035. Requiring changes sooner will start the transition away from fossil fuel systems that threaten our climate and public health.

As signaled by the UN International Panel on Climate Change, the next 10 years are critical to act on the climate crisis. We believe the 2035 net zero schedule puts us on the right track to build a climate-resilient Cambridge that is healthier and more equitable for all residents.

With the strongest Beudo amendments possible, over the next 10 to 15 years Cambridge can take a very big chunk out of local emissions and become a national leader. The amendments will be discussed at the council’s Ordinance Committee hearing at 5:30 p.m. April 20. We encourage everyone to contact councillors in support.

To register your support, simply send an email to [email protected], copying [email protected].

Kristine Jelstrup, Elena Fagotto, Lowry Hemphill and Margery Davies, Mothers Out Front, Cambridge


Mothers Out Front is a national organization working to ensure a livable climate for future generations.