The Santa Rita Jail in San Francisco's East Bay area, has a 1.2 megawatt rooftop solar photovoltaic system, and a 300 kW solar tracking system to create a self-sustaining smart grid. If a disruption in the utility grid occurs, the jail automatically disconnects from the grid to use its stored energy, a capability called "islanding."

The Santa Rita Jail in Alameda County, the third-largest facility of its kind in California, and the fifth-largest in the nation, is the first jail in the U.S. to build its own smart grid. The $11.7 million project gives the jail a supply of reliable electricity for daily operations and security, while saving the county approximately $100,000 per year in energy costs. One way the jail saves is by operating off the electrical grid during the high-peak electrical rate hours, and charging the energy storage system during off-peak hours.

The prison requires three megawatts (3,000,000 watts) of electricity a day to sustain the 1 million sq. ft. facility. Energy efficiency and renewable energy elements include a 1.2 megawatt rooftop solar photovoltaic system; a 300-kilowatt solar tracking system; five 2.3 kW wind turbines; a one-megawatt fuel cell power plant with heat recovery for facility hot water and space heating (3,600 million BTU solar hot water system).

Chevron Energy Solutions, a subsidiary of Chevron Corp. designed, developed and built the project, which was funded in part by the U.S. Department of Energy, the California Energy Commission and the California Public Utilities Commission. Project funders included the California Energy Commission's Public Interest Energy Research program, the U.S. Department of Energy and the California Public Utilities Commission.