150820-N-LV331-003 SAN DIEGO (August 20, 2015) Secretary of the Navy (SECNAV) Ray Mabus, center, signs an agreement with Western Area Power Administration and Sempra U.S. Gas & Power to construct a 210 megawatt direct current solar facility. The agreement was signed last month and is the largest purchase of renewable energy ever made by a federal entity. (U.S. Navy photo by Mass Communication Specialist 2nd Class Armando Gonzales/Released)