Municipal Energy Storage Case Study | City of Chino Hills Public Works
How the City of Chino Hills, California deployed a Fortress Power eSpire commercial battery storage system to reduce energy costs, maximize solar utilization, and protect the critical municipal operations that serve an entire community.
Location: Chino Hills, CA
Clients: City of Chino Hills — Public Works Department
System Size: 280 kWh
System Components: Fortress Power eSpire 280 | 125 kW Inverter | 100 kW Solar PV Array | Keystone EMS
Installation Partners: RES | Willdan | EVA Green Power | Franklin Energy
Application: Energy cost savings, solar utilization, critical load backup
The Need
A city yard is one of its most operationally essential facilities. The Chino Hills Public Works Department uses its city yard as the central hub for the vehicles, equipment, and staff that keep the municipality running: road maintenance crews, utility operations, fleet services, facilities management, and public works administration. It is a working operation that supports city services around the clock.
The scope of what that means in Chino Hills is significant. The Public Works Department maintains 44 parks, 48 miles of trails, and more than 3,000 acres of open space across the city, in addition to roads, infrastructure, and municipal facilities. Keeping that level of service running depends on a reliable, well-equipped base of operations at the city yard.
Like many California municipalities, Chino Hills faces persistent pressure from rising utility costs and a mandate to move toward cleaner, more sustainable energy use. The city had already invested in on-site solar generation, but without battery storage, the value of that solar was limited. Energy generated during peak production hours could not be stored for use during periods of higher demand or utility rate peaks, and the facility had no reliable backup for critical loads in the event of a grid interruption.
The city needed a commercial energy storage solution that could work alongside its existing solar array, reduce electricity costs through smarter energy management, and ensure that essential facility operations remained protected when it mattered most.
The Solution
A team of four experienced energy partners plus Fortress Power collaborated to design and deliver the system: RES, Willdan, EVA Green Power, and Franklin Energy. The Fortress Power eSpire 280 was selected as the commercial battery energy storage system at the center of the project.
The system is configured in AC coupling, integrating cleanly with the facility’s existing 100 kW solar PV array without requiring changes to the solar infrastructure. The eSpire charges primarily from solar generation, maximizing the city’s return on its renewable investment by storing clean energy rather than sending excess generation back to the grid. The battery can also charge from the grid when needed, providing additional flexibility for off-peak charging and ensuring the system is always ready to perform.
Energy management across the entire system is handled by Fortress Power’s Keystone EMS, which provides centralized monitoring, battery controls, and intelligent dispatch. Keystone gives facility operators a single platform to oversee battery state of charge, solar production, and overall system performance, supporting both day-to-day energy cost optimization and longer-term reporting on savings and sustainability outcomes. The system is configured with no BESS export, keeping stored energy focused entirely on on-site use and cost reduction.
The installation was completed in just two months.
Results
The Chino Hills city yard installation delivers across all three of its core objectives. On-site solar generation is now stored and deployed intelligently, reducing the facility’s draw from the utility grid during peak rate periods and directly lowering monthly electricity costs. The no-export configuration ensures that every kilowatt-hour stored in the eSpire is used on site, maximizing the return on the city’s solar investment.
For the critical loads that support daily municipal operations, the eSpire provides a reliable backup layer. Should a grid interruption occur, the system is configured to support essential facility functions, keeping operations running and giving the Public Works team the continuity they need to maintain service across 44 parks, 48 miles of trails, and thousands of acres of open space without interruption.
The Keystone EMS ties it all together, giving the city a transparent, data-driven view of system performance that supports ongoing energy management decisions and helps demonstrate the value of the investment to city leadership and stakeholders.
A Model for Municipal Energy Storage
The City of Chino Hills project shows how municipal facilities can take a practical, high-impact approach to commercial energy storage: pair existing solar with intelligent battery storage, protect critical operations, and drive meaningful reductions in energy costs, all without a lengthy or disruptive installation process.
For cities and public agencies looking to reduce utility costs, meet sustainability goals, and strengthen the resilience of essential facilities, the Fortress Power eSpire platform offers a proven, scalable path forward.
Ready to explore what a commercial solar + storage system could do for your facility? Start a C&I Project Quote.
