Montgomery County Launches Clean Energy Microgrid for Electric and Hydrogen Buses

Montgomery County officials and state leaders have announced the completion of a major clean energy microgrid at the David F. Bone Equipment Maintenance and Transit Operation Center in Derwood. Described as the largest transit depot microgrid in the United States, the project is designed to facilitate the county’s transition to a zero-emission bus fleet by 2035.

The 6.8-megawatt system integrates thousands of solar panels, battery energy storage, and charging infrastructure. This configuration allows the northern transit depot to operate independently from the broader electrical grid during power outages, ensuring that transit operations can continue without interruption.

The microgrid is capable of supporting multiple buildings and up to 200 Ride On buses. According to officials, the system will help the county manage energy demand, reduce overall emissions, and improve the reliability of its transit infrastructure.

Transition to Electric and Hydrogen Fleets

The project supports a broader shift away from diesel-powered buses. David Dise, director of the Department of General Services, stated that the county currently operates about 70 electric buses within a total fleet of approximately 400 vehicles.

The county is now expanding its technology to include hydrogen-electric vehicles, which offer a longer range than standard electric buses. Mr. Dise indicated that the county expects to receive its first two hydrogen-electric buses in approximately two months, with an additional 11 vehicles arriving by the end of 2026.

These new vehicles will undergo a period of testing and staff training for drivers and mechanics before they are opened to the public. While the depot will initially utilize hydrogen gas purchased from an outside vendor, the county plans to eventually operate an electrolyzer to produce its own hydrogen from water.

Our push towards achieving the county’s climate goals has been in advance of the available technology to do so, in many cases.

David Dise, Director of the Department of General Services

Public-Private Partnership and Financing

The microgrid was developed through a public-private agreement between the Montgomery County government and AlphaStruxure, a Massachusetts-based company specializing in large-scale energy infrastructure. AlphaStruxure is backed by the D.C.-based global investment group Carlyle.

Under the terms of the agreement, AlphaStruxure is responsible for the design, construction, finance, and maintenance of the facility over the next 25 years. A building permit for the project lists construction costs at $48.6 million.

This collaboration follows a previous partnership between the county and AlphaStruxure for a smaller-scale microgrid at a bus depot in Silver Spring, which began operations in 2022.

Eric Coffman, director of energy programs for the Maryland Energy Administration, described the Derwood project as by far the most advanced clean energy project in the state and likely one of the most advanced in the country. Mr. Coffman noted that he hopes other counties will replicate this model by leveraging private capital to fund similar infrastructure.

The project is expected to support the planned expansion of the county’s Bus Rapid Transit network and strengthen overall climate resilience in the region.