BAE Systems powers Green Bus Zones in San Francisco and beyond to help cities get to zero emissions

Dec. 13, 2019
The Series-ER bus can switch from a combustion engine to driving on electric power through the green zones to limit emissions.

The San Francisco Municipal Transportation Agency (SFMTA) has selected BAE Systems to supply electric power and propulsion systems for its transit buses.  

The Series-ER (Electric Range) system will operate on 68 transit buses and create designated zones throughout San Francisco that are free of emissions. The Series-ER system targets these hot spots to reduce emissions and improve air quality in the areas where people live, work and visit. 

The system opens a new door for San Francisco to get to zero emissions by 2035, as each bus will now be able to drive on clean electric power through each of the areas – known as “green zones.” Buses can now switch to battery power from a combustion engine, temporarily eliminating diesel emissions when they cross the threshold of a green zone. The technology allows the city to convert the fleet into part-time electric buses as an intermediate step to full electrification. 

“This technology helps San Francisco get one step closer to full zero emissions operations, improving the health of the city’s environment and its residents,” said Steve Trichka, vice president and general manager of BAE Systems’ Power and Propulsion Solutions business. “With Series-ER, buses are programmed using global positioning software to turn off the bus engine once it enters the green zone and operate solely on electric battery energy.” 

The green zones — nine in total — are in population-dense neighborhoods most affected by air pollution. Each of the zones have a large presence of traffic that is contributing to a high rate of air pollution, according to the company.