The Pentagon has announced it will be installing a solar panel array on its roof in a historic first that’s part of a new $55 million Department of Defense clean energy initiative at military installations in the United States and Germany.

The DOD has been active in attempting to mitigate the large carbon footprint caused by the U.S. military with similar conservation strategies for several years. The money for the new solar panels is being sourced from a larger Department of Energy program that will spend $104 million in total on 31 projects affecting ten other federal agencies. The DOD says this is necessary to bolster its energy resilience and defense operational capabilities while also improving the quality of life for service members living and working at bases full-time.

"We have a moral obligation to the people that defend our nation, to their families and to the American people to provide modern and efficient facilities," Secretary Kathleen Hicks said in a DOD news release.

"As we think about the potential for making our homes and offices more energy-efficient, the world's second-largest office building is a pretty good place to start," U.S. Department of Energy Secretary Jennifer M. Granholm added in reference to the Pentagon.

(The White House first installed solar panels in 1979 under the Carter administration h/t ThoughtCo.)

The announcement is the first of three disbursements from the $250 million provided for the Energy Department in the 2021 Bipartisan Infrastructure Law.