Solar energy is playing a growing role in the military’s grand plan to use more clean power and rely less on local utilities to supply power to its bases.

U.S. military strategies are often cloaked in secrecy, but the American military’s very public plan to use more clean power offers a bright spot for solar companies, from tech startups to project developers. It’s not just on the rooftops of military facilities, but soldiers on the battlefield are interested in clean power technologies as a strategic tool for off-grid, light-weight combat.

In his plan to fight climate change last week, President Obama reiterated how the Department of Defense, the largest energy use in the country, plans to install 3 GW of clean power at its facilities by 2025. At the same time, over in New Mexico, SolarCity recently installed solar panels on 600 military homes as part of its larger, 5-year plan to put solar panels on roughly 120,000 military homes across the country, the California company said Wednesday.

The military also embraces the concept of the microgrid, which involves installing power generation equipment and storage to create a self-sustaining electricity network within a base. The goal is to be able to run the base operation when there is a blackout or other problem with the grid managed by the local utilities. “Every single military base in the U.S. plans to create a microgrid,” said Peter Asmus, an analyst with Navigant Research, explaining, “They don’t want to be at the mercy of utilities, in a war or in a  storm.”

The Army inaugurated its first microgrid at Fort Bliss, Texas, in May this year. The $2.4 million pilot project produces solar power and comes with energy storage to bank the solar electricity when it’s not needed. The project is only powering part of the base.

The military also is supporting solar power projects even if they are not designed to be part of any microgrid. As of early this year, over 130 MW of solar panels had been installed at military bases in at least 31 states, according to the Solar Energy Industries Association. So far, the Navy is producing more solar energy than the Army or the Air Force.

The Navy has over 58 MW at or near its bases in 12 states and Washington, D.C. The Army followed with roughly 36 MW.  But the Air Force boasts one of the earlier solar installations in the country: it inaugurated the 14MW project at the Nellis Air Force in Nevada in 2007.

Last summer, then Defense Secretary Leon Panetta and the then Interior Secretary Ken Salazar signed a memorandum of understanding to encourage renewable energy generation on up to 16 million acres that have been historically restricted to military use. The defense wants to attract private developers and investors to build solar, wind and other renewable energy projects. It plans to buy some or all of the power from these projects for its own use and sell unused power to local utilities.

On the battlefield, supplying fuel to soldiers is both costly and risky. In addition, a soldier’s pack could weight over 100 pounds when the pack includes batteries for communication and safety. That makes any light-weight and portable sources of energy desirable for the military, which also has the budget and willingness to buy high-tech and newly developed gear from startups.

Venture-backed Alta Devices, for example, is targeting the military with battery chargers that feature its highly efficient solar cells. Semprius, another solar cell startup, lined up Pratt & Whitney Rocketdyne as a customer to take part in a defense project.

HHaving the military and defense industry in its corner, is a major boon for the clean power companies and project developers. In a market where clean power can be more expensive than fossil fuel power in some areas, a customer of the size of the military can help bring down the cost of solar by buying and installing it at scale.