A plan to introduce a new battery-powered electric train propulsion system to the Fairmount Line approved today by the MBTA’s board of directors is being hailed by advocates and state political leaders. Supporters say the $54 million proposal will bring faster, cleaner service to the commuter rail line by 2028.

The Fairmount Line includes multiple stations in Dorchester and Mattapan, including Blue Hill Avenue, Talbot Avenue, Four Corners, Morton Street, Uphams Corner and Newmarket. It has been greatly enhanced with several new stations and additional frequency in the last ten years.

"This plan is a major win for Fairmount Line riders and our entire state,” said Gov. Maura Healey. “By electrifying the Fairmount Line, we'll deliver more frequent, reliable service while also moving Massachusetts forward on our climate goals.”

The approval of the new technology — known as battery electric multiple units or BEMUs— was recommended by the commuter rail operator Keolis in 2023 and won initial approvals earlier this year. Advocates say it will eventually allow for 20 minute intervals between Fairmount trains during peak times.

“Subject to the procurement process, the first train is expected to enter service on the Fairmount Line in early 2028,” according to a statement from the MBTA after the vote.

Jarred Johnson, executive director of TransitMatters, called it a “a monumental step that represents the first real commitment to the Regional Rail vision laid out five years ago.

Johnson added: “We're excited that the T is partnering with Keolis to test new technology that allows us to electrify the service faster and bring tangible benefits to riders.”

MBTA general manager Philip Eng said the decision was a “gamechanger.”

“By embracing new technologies, we will be able to electrify the Fairmount Line sooner within our existing available funding. Understanding the billions of dollars needed to fully electrify our entire system, this is the first step that I believe will pave the way to a profound transformation that can bring the future of our rail network that much closer,” Eng said.

“We’re thrilled that our proposal has been approved and that we are able to partner with the MBTA to introduce decarbonized service to the Fairmount line community,” said Abdellah Chajai, GM and CEO of Keolis Commuter Services. “Battery-electric trains will transform the Fairmount Line, allowing for more frequent trips, more reliable service, and reduced carbon emissions.”