Santa Clara VTA rolls toward cleaner, greener future fleet

Jan. 28, 2022
Santa Clara VTA partners with Proterra and Scale Microgrid Solutions to charge 34 electric buses with a solar-powered microgrid.

The Santa Clara Valley Transportation Authority (VTA) is making a big step to transitioning to a newer, quieter and zero-emission bus fleet thanks to a grant award from the California Energy Commission’s Clean Transportation program.

The $4.7-million grant award completes the funding needed for a $16.4-million project that will install 34 new bus chargers, solar panels and a microgrid at Santa Clara VTA’s Cerone Bus Yard.

To compete strongly for grant funding, the authority says it partnered with Proterra, which brings expertise in battery design and bus charging; Scale Microgrid Solutions, a provider of microgrid design and construction; and Lehigh University, whose Institute for Cyber Physical Infrastructure and Energy has been working in the “smart grid” space for nearly a decade.

The project is on track to come online in late 2023 and will support Santa Clara VTA’s next battery-electric bus purchase. The authority’s current electric bus fleet consists of five 40-foot Proterra buses, with five more on the way. Upon completion, the new charging infrastructure will be able to fully charge a bus in as little as four hours. Together, the infrastructure and new buses will provide a better experience for riders, be better for the environment and save VTA operating costs.

A more pleasant riding experience

Battery-electric buses are quiet which makes them much easier places to relax, read, work or listen to music than diesel buses. This project is the first step in transitioning to an entirely zero-emission fleet, a state mandate that Santa Clara VTA must comply with by 2040. The chargers designed by Proterra can be easily replicated to serve future battery-electric bus purchases. As the decade progresses, riders will see fewer diesel buses and more of the authority’s new, quieter electric fleet.

Cleaner and greener transit service

The new fleet will not emit exhaust and will be powered largely by green energy collected by new solar panels. This helps us decrease our carbon footprint and meet the goals of increasing renewable energy use adopted by Santa Clara VTA’s Board in the 2020 Sustainability Plan. It also helps improve local respiratory health. Per state guidelines, and in line with Santa Clara VTA’s equity platform, these buses will serve areas with worse-than-average air quality and higher-than-average rates of respiratory health ailments, like East San Jose.

Operating cost savings

This project allows Santa Clara VTA to save on operating expenses in a few ways. The solar panels decrease the amount of electricity Santa Clara VTA needs to buy from utilities. For the electricity it still must purchase, Santa Clara VTA can buy it off-peak when rates are cheaper, store the electricity in the microgrid battery and charge buses when convenient. Electricity is a more cost-effective way to power buses than diesel. Altogether, Santa Clara VTA projects to save about $1.2 million a year in energy costs, which is a savings that can be put toward other operating needs, like transit service.

Resiliency and emergency support

The microgrid gives Santa Clara VTA a backup energy source if there is a prolonged power disruption. In the event of an extended power outage, such as a public safety power shutoff, electricity stored in the microgrid’s battery storage system can provide back-up power to allow the agency to continue operating battery-electric buses, serving riders and providing emergency transport if needed.

In conjunction with Proterra and Scale Microgrid Solutions, Santa Clara VTA will deploy approximately one-and-a-half megawatts of solar on-site via available rooftop space and an overhead carport canopy at the agency’s Cerone bus yard. The solar PV is paired with a battery storage system that can store four-megawatt hours of usable electricity and one megawatt of peak output power to provide back-up electricity at the bus yard for up to 20 hours of emergency operations. For extended outages, Santa Clara VTA has the option to easily connect a temporary generator to provide additional backup power for fleet operations. The agency will also install two Proterra one-and-a-half megawatt fleet chargers to power 34 electric transit buses.

The microgrid and charging infrastructure will be linked together by a switchgear and controls package designed by Schneider Electric for robust and dependable operations.