On April 28, with support from the National Renewable Energy Laboratory (NREL), the U.S. Department of Energy (DOE) kicked off the Solar Desalination Prize, a $9 million competition that’s part of the American-Made Challenges series.

The competition is designed to accelerate the development of systems that use solar-thermal energy to produce clean drinking water from salt water.

NREL manages each of the American-Made Challenges for the DOE.