Montgomery County, Maryland began construction on an integrated microgrid infrastructure project that will feature electric bus charging and on-site green hydrogen production powered by solar and battery energy storage.

The county operates the second-largest bus fleet in the Washington, D.C. region. The David F. Bone Equipment Maintenance and Transit Operations Center is a major depot within Ride On Montgomery’s network and the fifth largest county-owned energy consumer. 

By 2035, the depot is projected to accommodate 200 zero-emissions buses with most of them being hydrogen fuel cell electric buses (FCEBs). A hydrogen FCEB is a zero-emissions vehicle, powered by hydrogen and oxygen, emitting only water.

The microgrid’s construction is expected to be completed in 2025. AlphaStruxure, an Energy as a Service (EaaS) microgrid solutions company when the system will begin sending renewable energy back to the grid and have the ability to power zero-emissions buses. 

“This project is the largest renewable energy-powered transit depot and transit depot microgrid in the nation; it is also the first facility on the East Coast to produce green hydrogen on-site,” said County Executive Marc Elrich in a statement. “It is great to see this bus depot microgrid move from concept to construction so quickly thanks to our ongoing partnership with AlphaStruxure and their related companies; we already have five microgrids in operation or development, with more underway..”

Fueling the county’s FCEBs with green hydrogen produced by the microgrid’s solar array advances the county’s goal of reaching a 100% reduction in carbon emissions by 2035. The microgrid also enables the county to reduce its Scope 1 and 2 emissions by 4,000 metric tons of CO2 annually.

The microgrid will provide sustainable, resilient power to a mixed fleet of battery electric and FCEBs, along with the facility’s five buildings. It will also be interconnected to the Pepco utility grid.

The microgrid will include the following:

• 5.65 MWDC of rooftop and canopy solar generation
• 2 MW/6.88 MWh battery energy storage
• Up to 2.25 MW of charging capacity
• 1 MW hydrogen electrolyzer

In addition to powering on-site production of green hydrogen, a resilient fuel source for FCEBs, the microgrid will also be able to send up to two megawatts (MWs) of renewable energy back to the utility grid via a Pepco net metering program.