The U.S. military spends $20 billion a year to power its facilities, vehicles and overseas bases, and most of that energy comes from non-renewable sources such as coal, oil and gasoline. This system has numerous drawbacks. Besides the fact that these fuels pollute the atmosphere, they are expensive to transport to combat zones. A report from the Solar Energy Industries Association (SEIA), a trade group that advocates on behalf of the solar sector, states that although the Armed Forces pay about $1 a gallon for gasoline, it costs $400 per gallon to transfer that fuel to outposts in Afghanistan where it is consumed.
But according to SEIA, the military is moving toward renewable energy as a major source of its power needs. The report also states that the Department of Defense has plans to derive 25 percent of its energy consumption from renewable sources such as wind and solar power by 2025. There are currently 58 megawatts (MW) of installed solar capacity for the Navy, 38 MW for the Air Force, and 36 MW for the Army. At the same time, all three branches plan to build a combined 3 gigawatts (GW) of renewable energy capacity by 2025, of which 1.9 GW will be solar panel arrays.
There are many reasons for the military to pursue these goals. In addition to concerns about anthropogenic climate change caused by fossil fuel burning, it is also very dangerous to transport oil and gasoline into combat zones because fuel convoys are often targeted by the enemy.