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 first article in a series exploring the evolution of mass transit throughout the Bay from a building trades perspective. This month, we focus on SF Muni’s trolleybuses.
Muni’s Overhead Lines Could Play Key Role in a Greener Future
By Robert Fulton, contributing writer
With the San Francisco Municipal Transportation Association (SFMTA) — which runs Muni — pushing for a zero-emission transit fleet by 2040, a local think tank has proposed a radical concept: Why not utilize, upgrade, and expand a resource that already exists in the City?
The Climate and Community Project (CCP), a climate policy think tank, recently released a report called “San Francisco Muni Electrification Alternative Analysis.” Its results conclude that “maintaining and expanding San Francisco’s trolleybus fleet with [in-motion-charging] technology could be the fastest and most efficient way to decarbonize” the Muni system.
In other words: There’s a better option than spending a boatload of cash on a fleet of all-electric, battery-powered buses using technology with known limitations. Instead, Muni can create more electrified routes by expanding and improving overhead catenary lines used by trolleybuses.
“San Francisco’s existing overhead line system is an invaluable resource that SFMTA should exploit fully as it electrifies its fleet,” IBEW Local 6 Business Manager John Doherty said in a press release announcing the CCP report, which the IBEW participated in crafting.
At the end of 2018, the state’s air quality management agency, the California Air Resources Board (CARB), adopted regulations requiring public transit agencies throughout the state to 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, SFMTA presented a rollout plan to CARB to transition Muni’s bus fleet to 100% zero-emission. The plan calls for the procurement of battery-powered buses.
The prevailing thought expressed in the CCP report, however, is that using and expanding the existing trolleybus lines would in fact be the easier and more efficient route to take. According to the 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.
Better technology is also an asset in improving the overhead catenary system. In-motion-charging trolleybuses come with on-board batteries and do not need overhead wires for their entire routes, allowing them more flexibility.
And, of course, a well-trained and experienced workforce is in place to expand and maintain such overhead lines.
“This report shows that leveraging our overhead line system to electrify SFMTA’s bus fleet is not only the most practical way to eliminate transit-related diesel exhaust as soon as possible but is also fiscally responsible to taxpayers and riders,” Doherty said.
San Francisco’s trolleybus system first started operating in 1935. The system now boasts 12 routes traversed by 185 standard and 93 articulated buses, and it utilizes hydroelectric power.
One concern with a fleet of battery-only buses is that the charge isn’t strong enough to complete a shift, necessitating a more extensive fleet.
Alex Lantsberg is research and advocacy director of the San Francisco Electrical Construction Industry, the labor-management cooperation committee of IBEW Local 6 and the San Francisco Electrical Contractors Association. He co-authored the CCP report. He called the catenary lines a “priceless asset” and cautioned against falling in love with new technology that might not be a good fit for its intended use.
Speaking before SFMTA’s Board of Directors meeting on Tuesday, July 18, Lantsberg said, “Our catenary-powered rubber-tire fleet [is] ideally suited to San Francisco’s challenging operating environment, and orienting a decarbonization plan around a battery-powered fleet would not serve San Francisco well.”
Lantsberg sees using, upgrading, and expanding the Muni trolleybus system as a good alternative with multiple benefits that go beyond simple common-sense solutions to deliver better-quality transit overall.
“When our transit system works well and is efficient and gets people where they need to go, it makes the City a much better place to do business,” he said.
