Four resourceful teenagers from Nigeria have created a generator that runs on a material easily found in any part of the world—pee.

14-year-olds Duro-Aina Adebola, Akindele Abiola, Faleke Oluwatyoin, and 15-year-old Bello Eniola created their urine-powered generator as part of Maker Faire Africa, a startup event held in Lagos, Nigeria that highlights African innovations and inventions.

The device works by separating out the hydrogen from urine and using it to power the generator.

The Next Web explains how the contraption works in more detail:

•Urine is put into an electrolytic cell, which cracks the urea into nitrogen, water and hydrogen.

•The hydrogen goes into a water filter for purification, which then gets pushed into the gas cylinder.

•The gas cylinder pushes hydrogen into a cylinder of liquid borax, which is used to remove the moisture from the hydrogen gas.

•This purified hydrogen gas is pushed into the generator.

•1 Liter of urine gives you 6 hours of electricity.

Although incredibly inventive, the girls’ device isn’t quite ready to power up a house just yet. As Co.Exist points out, the separation of hydrogen from urine still requires an outside source of electricity. Another issue is safety, Forbes notes, since hydrogen poses an explosion risk. Still, there’s no doubt that the teens are on the right track when it comes to thinking about creative ways to harness energy.