The Department of Energy will enter into lease negotiations with two solar energy developers for 400 megawatts of solar electricity generation within the Idaho National Laboratory site. Announced on June 5, the projects are the first proposed projects selected under the department’s Cleanup to Clean Energy initiative, an effort to repurpose parts of DOE-owned lands—portions of which were previously used in the nation’s nuclear weapons program—into sites of clean-energy generation, including for solar, geothermal, wind, and nuclear.

Cloud cover cuts solar generation, and on calm days wind turbines won’t spin. When cloudy and windless conditions coincide for hours or days, the result is called a compound energy drought. Pacific Northwest National Laboratory recently found that these energy droughts can last nearly a week in some parts of the country and that they overlap with periods of peak grid demand more often than would be expected by chance.