The Navy announced Thursday that it will buy power from a sprawling solar farm in the Arizona desert to help power 14 military installations in California, in the largest renewable energy purchase by the U.S. government to date.

San Diego-based Sempra Energy expects to have the Mesquite 3 solar facility online in 2016. The 150 megawatt solar array is being built at a power complex 60 miles west of Phoenix, and has the capacity to power nearly 100,000 California households at one time by one common measure.

The Western Area Power Administration, which markets and delivers hydroelectric power across 15 states, helped broker the power contract, which will supply a third of the power to 14 Navy and Marine Corps installations, including Naval Base Coronado.

Financial terms of the 25-year power purchase agreement were not available.


The U.S. military is turning increasingly to renewable energy technologies such as solar and biofuels to trim dependence on fossil fuels and, in many instances, save money.

The Navy last year arranged for rooftop solar power at nearly 6,000 housing units in the San Diego area occupied by Navy and Marine Corps personnel.

Navy Secretary Ray Mabus will attend a ceremonial signing for the new solar contract at Naval Base Coronado next week, along with Sempra U.S. Gas & Power President Patti Wagner.