It’s not just about climate change. Renewable energy has many benefits beyond low carbon emissions and a free, unlimited source of naturally occurring power.

The concept of national energy security also arises when discussing the need to limit the United States’ fossil fuel dependence. Most understand that a greater reliance on renewables will help make the country independent from oil-supplying countries and distance it from Middle East politics. However, renewable power also offers tactical potential to the U.S. armed forces.

U.S. Secretary of the Navy Ray Mabus recently announced a partnership between the Department of Defense and the Department of Energy’s Advanced Research Projects Agency-Energy (ARPA-e). Apparently, the military is already generating renewable power, but storing it has proven problematic. The partnership will capitalize on technology breakthroughs to transform the way the military stores power generated from renewable sources.

“What we don’t have and what we need is the ability to store the energy we create,” Mabus said in his keynote address at the ARPA-e Energy Innovation Summit in Washington, D.C.

The collaboration Mabus announced will focus on two key developments affecting renewable-energy storage. The first involves hybrid energy-storage modules that can be applied to store the energy troops need to power equipment, which is currently running on solar power. Much of that power goes to waste now because of inadequate storage capacity. The new hybrid modules are an innovation in battery technology that houses large amounts of energy in very lightweight materials.

The second element of this collaboration focuses on improved energy storage at the grid level. Currently, military bases and other installations that depend on the commercial grid for power are vulnerable to outages and disruptions. Grid-scale storage across installations would enable facilities to maintain critical operations in the event of a disruption and to develop microgrids for improved energy security.

The partnering agencies are requesting $25 million for each of the two projects. The effort is expected to be initiated during the 2012 fiscal year.