The Wind-to-Battery Project shows the need to compensate for wind variability can be reduced. The small demonstration project - the first U.S. use of the sodium sulfur battery-storage technology as direct energy storage - is part of Excel's research on integrating unpredictable renewable energy into the grid.
Begun in October 2008, the research is being conducted with a battery installation in Luverne, Minnesota, connected to a nearby 11-MW wind farm. 20, 50 kW battery modules weighing about 80 tons can store 7.2 MW-hours of electricity, with a charge/discharge capacity of 1 MW. Fully charged, the battery can power 500 homes for over seven hours.
Preliminary tests indicate the technology can shift wind energy from off-peak to on-peak availability, and can support the regional electricity market by responding to real-time imbalances between generation and load. The system could provide voltage to the grid, which would contribute to system reliability, according to Xcel Energy. Testing will continue to see how the battery system handles larger amounts of wind energy transfers to the grid.
The next phase of the project will evaluate the technology's cost effectiveness. A final report is expected in summer 2011. See the Xcel Energy press release and the Wind-to-Battery report (PDF 2.94 MB).
Bay Area Gets $5 Million for EV Charging Stations
On August 5, the Bay Area Air Quality Management District (BAAQMD) in San Francisco approved $5 million to fund further development of a regional electric vehicle (EV) charging infrastructure program. The stations and home chargers are part of the BAAQMD's "Spare the Air" program, designed to make owning EVs viable in the Bay Area.
The program will support EV charging infrastructure grants for 3,000 home chargers at single family and multi-family dwellings. The grants will also supply 2,000 public chargers at employer and high-density parking areas and 50 fast chargers near highways. According to the BAAQMD, transportation accounts for over 50% of the air pollution in the region. See the (BAAQMD press release) and the BAAQMD Web site.
$117 Million Loan Guarantee for Hawaii Wind Project
On July 27, DOE announced it finalized a $117 million loan guarantee for Kahuku Wind Power, LLC, and its 30 MW Kahuku Wind Power project in Hawaii.
The project includes development of an innovative wind plant that will supply electricity to about 7,700 households a year. According to company estimates, the project, located on Oahu's North Shore, will create more than 200 wind jobs on the island. The project will be the first to meet reliability requirements for wind and solar energy set by Hawaiian Electric Company, the only electric utility operating on Oahu.
The project, which began construction in July, uses 12, 2.5 MW Liberty wind turbines manufactured by Clipper Windpower and a 10 MW battery energy storage system that will modulate and smooth fluctuations in power output caused by changes in wind levels.
First Wind Holdings, LLC, the project sponsor and an independent U.S.-based wind developer, built and operates Hawaii's largest wind facility, the 30 MW Kaheawa Wind project on Maui, which generates 9% of the island's electricity needs. See press releases from DOE and First Wind, and the DOE Loan Guarantee Program Web site.
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EREE Network News is a weekly publication of the U.S. Department of Energy's Office of Energy Efficiency and Renewable Energy (EERE).
