An SF Muni trolley bus on the 14 Mission line makes a turn downtown in September 2015.
Mass Impact Logo

Mass Impact

The Bay Area’s mass transit infrastructure is some of the most extensive and highest in quality of any region in the nation. But for it to serve working people well and continue to thrive, it must grow and change.

This is the fourth article in an ongoing series exploring the evolution of mass transit throughout the Bay from a building trades perspective. This month, we focus on the future of Muni’s electrified trolley buses.

Muni Shifts Gears, Ensures Electrified Trolley Buses Have a Place in SF’s Future Mass Transit Fleet

By Robert Fulton | contributing writer

For whatever reason — careful consideration, overwhelming evidence, or recent articles published in this newspaper — the San Francisco Municipal Transit Authority (SFMTA) has shifted gears regarding the future of the City’s iconic and long-standing trolley bus fleet.

The SFMTA runs Muni. It’s aiming for a zero-emission transit fleet by 2040. Recent votes by the agency seemed to indicate that it was planning to retire and replace its entire stock of trolley buses, which are powered by overhead electrical wires also known as catenary lines, with all-electric plug-in-battery-powered alternatives.

But last November, the SFMTA changed lanes and announced that it would be including the trolley buses in its zero-emission plan for the future.

Three months prior, in August 2023, Organized Labor published an article that cited a report from the climate policy think tank Climate and Community Project (CCP) questioning the utility of a battery-powered-bus-only fleet. The CCP report advocated for not just the retention but the expansion of trolley buses in public transit fleets.

The IBEW helped to craft that report.

“We were effective in getting that message out there,” said IBEW Local 6 Business Manager John Doherty of the push to keep trolley buses gliding around the City. “Saving the trolley bus system is definitely a good outcome for Local 6, the SFMTA’s move to 100% emission-free transit, and those who rely on public transit in San Francisco.”

Local 6 members in the 7371 Electrical Transit Mechanic class series have performed the maintenance and repairs on Muni’s all-electric fleet since 1918. Today, that all-electric fleet includes streetcars, light-rail vehicles, trolley buses, and the SFMTA’s historic cable car fleet.

That’s a lot of work. It should go without saying that the City’s union electricians are invested in keeping around as much of the electrified Muni fleet as possible.

At the end of 2018, the state’s air quality management agency, the California Air Resources Board (CARB), adopted regulations requiring public transit agencies statewide transition to 100%-zero-emission bus fleets by 2040; beginning in 2029, all new purchases by transit agencies must be zero-emission buses. In 2021, the SFMTA presented a rollout plan to CARB to transition Muni’s buses to 100%-zero-emission.

The transit agency’s earlier plan called for the procurement of a battery-powered bus fleet. Battery-powered plug-in buses, however, come with numerous challenges. These include a limited range, San Francisco’s power-sapping topography, insufficient infrastructure, and high overall costs of operation and maintenance.

Trolley buses, which have been in use in San Francisco for more than 80 years, are already electrified. Improved technology in the form of in-motion charging allows for even greater range, as the buses can now go several miles off-wire between overhead catenary lines.

According to the CCP report, a mere 33% increase in overhead line infrastructure would allow Muni to more than double its zero-emission fleet and add 210 miles of electrified service to Muni riders.

Alex Lantsberg is research and advocacy director for the San Francisco Electrical Construction Industry, the labor-management cooperation committee of Local 6 and the San Francisco Electrical Contractor’s Association. He worked on the CCP report and has been an outspoken supporter of the trolley bus system over plug-in electric.

“By leveraging the use of trolley buses — especially in San Francisco, where you really have this great asset that you can electrify faster and cheaper — it would be better operationally, and, ultimately, it’s better environmentally,” Lantsberg said. “So, [maintaining a trolley bus fleet is] the environmentally, economically, and operationally superior alternative.”

That said, it’s not as if the City’s public transit system is the reason the polar ice caps are melting. According to SFMTA Director of Transit Julie Kirschbaum, Muni accounts for a tiny fraction of San Francisco’s total carbon emissions.

The City’s transit system currently includes diesel hybrids. Woods Bus Yard has been fitted with charging equipment for the battery buses currently being tested. Future plans for the Kirkland Bus Yard include upgrading it to electric. The transit system receives its 100%-renewable power from the Hetch Hetchy Project.

“We are already one of the most successful low- and zero-emission systems in the country,” Kirschbaum said. “That’s something we’re really proud of.”

The SFMTA isn’t abandoning the plug-in-battery-powered bus concept either. Kirschbaum stressed that the agency’s new policy takes something of an all-of-the-above approach to meet its emissions goals. Muni already has 12 battery-powered buses out on the road, and the SFMTA has secured a grant to acquire 18 more.

Of the agency’s change in policy, Kirschbaum said: “We’re really focusing on trolley buses and battery electric buses, but it could, in the future, allow us to consider [hydrogen] fuel-cell buses or even something new that hasn’t been brought to market yet. They wanted to give us flexibility because we have a diverse set of needs and constraints.”

It seems that trolley buses won’t be riding off into the sunset after all.

Organized Labor


Sign Up Now


Go to top