Pennsylvania leads nation in power grid battery storage
While the electricity flowing through area homes usually comes from coal-fired, natural-gas fired or nuclear power plants, it occasionally could come from batteries.
The regional grid that powers Pennsylvania homes and businesses, the PJM Interconnection , contains 49 percent of the nation's utility-scale battery storage power capacity, according to the Energy Information Administration.
The 274 megawatts of capacity in the region includes at least two facilities in Somerset County. The batteries in this region are mainly used to maintain the grid during sudden increases in electricity demand while other generator sources come online.
Consequently, they store an average of 12 megawatts but can sustain that power for only about 45 minutes, according to the EIA.
Batteries also can be used to store energy from intermittent sources such as windmills and solar panels.
The next largest accumulation of battery storage is in the California Independent System Operator grid, which contains about 16 percent of the nation's capacity.
The California facilities are used for a wider range of applications than the ones in the PJM Interconnection, so they average less power, about 5.7 megawatts, but can sustain it for an average of nearly four hours.
Brian Bowling is a Tribune-Review staff writer. Reach him at 724-850-1218, firstname.lastname@example.org or via Twitter @TribBrian.