The U.S. Department of Energy announced Wednesday that it will offer a $1.4 billion partial loan guarantee to Prologis and NRG Energy to install rooftop solar panels on company warehouses.

The AMP Project will install around 733 megawatts worth of solar panels on the rooftops of warehouses owned by Prologis. The electricity generated by the solar panels will then be sold to utility companies and distributed across the grid. It’s one of the U.S. Department of Energy’s largest loan guarantee commitments, though the department didn’t specify how much of the loan it would guarantee for the project.

NRG Energy will fund the first phase of the project, which will create a 15.4 megawatt array of solar panels in southern California. The company will create a power purchase agreement with Southern California Edison. When completed, Project Amp should generate enough electricity to power 88,000 homes, the Department of Energy said.

The Department of Energy offers loan guarantees to help companies attract buyers and investors for renewable energy projects. Under the guarantee, the federal government will foot the bill if the project does not take off or is unable to get some kind of return for investors.

The U.S. Department of Energy has committed a total of $33 billion in conditional loan guarantees to clean technology projects across the country. The department has committed $12 billion of that money to solar power projects.