Here Comes the Us’s Largest Self-Sustaining Renewable Bus Depot

Clean energy trailblazer Montgomery County, Maryland, has announced it’s building what will be the largest self-sustaining, renewable-powered bus depot in the US.

The bus depot will be an Energy as a Service microgrid – that means it will offer various energy-related services to consumers in addition to supplying electricity.

It’s known as Montgomery County’s Equipment Maintenance & Transit Operation Center, or EMTOC. The project, which was built by Boston-based Energy as a Service provider AlphaStruxure, is expected to begin construction in Q4 2023 and be in operation by Q1 2025. AlphaStruxure is a joint venture of Schneider Electric and Carlyle, and it’s financing the project through its Energy as a Service business model.

Montgomery County’s 7 megawatt (MW) microgrid will feature 5 MW of rooftop and canopy solar generation, 2 MW/7.35 MWh battery storage, existing backup generation, and up to 4.5 MW of charging capacity.

It will also have an onsite electrolyzer powered by solar and battery storage – making it the first renewable-powered bus depot on the East Coast to produce green hydrogen. That means EMTOC will be able to provide sustainable power for EMTOC’s five existing buildings, battery electric buses, and fuel cell electric buses.

The green hydrogen produced at EMTOC will power the county’s first 13 fuel cell electric buses – zero-emissions vehicles powered by hydrogen and oxygen that emit only water – used on longer bus routes. Those 13 fuel cell electric buses will reduce the county’s Scope 1 and 2 emissions by 4,000 metric tons of CO2 per year – equivalent to approximately 780 homes of electricity use for a year.

The microgrid will be interconnected to the Pepco utility. It will be engineered to operate indefinitely in “island mode,” ensuring uninterrupted service during power outages and emergency situations.

EMTOC is projected to accommodate over 200 mixed-fleet vehicles by 2035.

In October 2022, Montgomery County inaugurated Brookville Smart Energy Bus Depot, its first fully constructed microgrid-powered bus depot, which was also led by AlphaStruxure.