When It Comes to Restrooms, Solar Power is Number One

The recent launching of two floating restrooms on Lake Elsinore in Riverside County garnered much local media attention—the cabin-like structures are meant to give boaters a place for a bathroom pit stop when they are far from shore. But the floating facilities are also notable for how they work: on solar power.

The Douglas fir buildings are stationed on floating platforms and have metal roofs topped with solar panels. An onboard reservoir stores pumped lake water for the toilets' water supply, and the low-flow toilets empty into a holding tank.

Lake Elsinore isn't the only recreation destination taking advantage of solar power for restroom facilities. New York beaches in Coney Island, Staten Island, and the Rockaways are getting prefabricated bathrooms with solar panels and skylights to replace facilities destroyed or damaged by Hurricane Sandy. And solar is used to power electrical systems or heat shower water at beaches and campgrounds across America, from Sanibel, Florida to Huntington Beach, California. (The first solar-powered public restroom, according to reports, was a $21,000 Colonial-style facility that opened in Narragansett, Rhode Island in 1979.)

Solar power is even transforming the humble port-a-pottie. Several companies offer rentals of solar-powered temporary toilet stalls—many of them billed as "luxury" facilities thanks to the capability of solar power to heat the water and light the restroom.

But solar's use in toilets can also be practical. Last year, a group from California Institute of Technology (Caltech) took the $100,000 first prize in the Reinvent the Toilet Challenge sponsored by the Bill & Melinda Gates Foundation. The purpose of the contest was to find new ways to build toilets that would work in developing nations, where defecation out in the open leads to severe sanitation and health problems. Caltech's winning idea was a solar-powered bathroom that uses the energy produced by the sun to power an electrochemical reactor that converts human waste into hydrogen gas. That gas, in turn, is stored in fuel cells and used as a backup energy supply for the bathroom.