With cost-sharing funds of US $1.5 million from the California Energy Commission, the Sacramento Municipal Utility District (SMUD) will begin demonstrating a new application for distributed energy resources known as a microgrid.
A microgrid is an integrated energy system consisting of interconnected electrical loads and distributed generation, such as photovoltaics (PV) or engines, which as an integrated system can operate in parallel with the electrical grid or in an intentional island mode. The design and construction work will begin in 2009 with the actual demonstration beginning in 2010. The demonstration will run for approximately 18 months. The total costs are nearly US $3 million.
SMUD will field demonstrate a 310-kW load microgrid at the utility’s corporate headquarters. For the demonstration, three 100-kW reciprocating engine generators will be coupled with a 12- ton absorption chiller system and an existing 10-kW PV system. Electrical output will be provided to the central utility plant and another building to serve sensitive loads such as the chilled and hot water distribution pumps, controllers, cooling towers and related equipment that need to continue operating during a utility electrical outage. The project is unique in that it will link natural gas fueled internal combustion engines with the PV system.