Alcatraz, located 1.5 miles out from Fisherman's Wharf in the San Francisco Bay, has installed a solar microgrid to mitigate costs. Just before the historic prison closed in 1963, an anchor cut the transmission line linking the island to San Francisco's electrical grid. When the NPS reopened the site years later, they installed a diesel-generator grid. In 2010, the island was shipping 2,000 gallons of diesel fuel weekly. The solar installation, completed this year, is already saving taxpayers money. Forbes reports:
Andy Walker, an NREL engineer who led the design assistance team for the project, told Bill Scanlon that before the solar-powered microgrid system was installed, the Park Service paid $0.76 per kWh for electricity on Alcatraz. The cost to taxpayers today is $0.71 per kWh, which includes the capital costs of buying and installing the rooftop PV system.