Eversource Breaks Ground on Largest Underground Electrical Substation in U.S.

Eversource, a New England-based energy provider, broke ground in Kendall Square on Tuesday on what will be the largest underground electrical substation in the United States.

The Greater Cambridge Energy Program, devised to establish necessary infrastructure 105 feet underground, will provide enough energy to replace 50 percent of the city’s commercial sector gas demand with electricity and electrify all of the city’s residential heating.

State Senator Sal N. DiDomenico, who attended Tuesday’s construction commencement celebration, said in an interview with The Crimson after the event that the substation is “critical” to Cambridge’s biotech development.

“We want to be a world leader in the life sciences and biotech, and we need infrastructure to make that happen,” he said. “The resiliency piece of it is an important part that no one sees.”

The project, which is a partnership between real estate investment company BXP, the Cambridge Redevelopment Authority, and the city of Cambridge, will also build 115 kV worth of underground transmission lines that will span 8.3 miles — sending electricity into Boston, Cambridge and Somerville. GCEP will also add 420,000 square feet of affordable housing to BXP’s Life Sciences Center.

“The success of this project is rooted in the relationships and the partnerships that made it happen,” BXP Senior Vice President of Development Jeff Lowenberg said.

The project, however, did not come to fruition without complaint.

Initially, Eversource planned to build the substation above ground — a plan that was met with concerns by Cambridge residents. The city of Cambridge then requested that the company find a new site for the project.

“The plan was to put the substation on Fulkerson Street, really bordering the residential area,” said David Maher, president of the Cambridge Chamber of Commerce. "It was just not the right place."

After developers proposed an underground substation plan at the new location between Binney and Broadway streets, both Harvard and MIT requested that Eversource “avoid the need to cross or make use of their properties and thereby constrain future redevelopment activities,” according to a June 2024 filing from the Energy Facilities Siting Board.

In October of 2023, MIT filed a formal request that underground cable routes not pass underneath Vassar Street, which runs through the center of the MIT campus, due to concerns that construction would affect students and research activity. The university also submitted evidence for alternative routes they argued were better than the Vassar Street option.

MIT’s requests were denied by the board.

Katherine Watkins, Commissioner of the Department of Public Works, said in an interview with The Crimson that finding the space for the transmission lines in dense utility corridors, especially considering the MBTA Red Line, was a major challenge.

However, the filing noted that MIT and Eversource are still in negotiations over mitigating disruptions to the university’s campus.

“We went through a number of iterations to find some alternatives that are much less impactful on the community,” Watkins said.

Despite the University’s concerns, Eversource CEO Joseph R. Nolan said in a speech at the event that people “all over the world” are excited about the substation.

“Nobody can quite believe that we’re able to do this,” Nolan said. “This city of Cambridge puts their money where their mouth is.”

—Staff writer Stephanie Dragoi can be reached at stephanie.dragoi@thecrimson.com.

—Staff writer Thamini Vijeyasingam can be reached at thamini.vijeyasingam@thecrimson.com. Follow her on X @vijeyasingam.