Soil lamp powered by mud

Dutch designer Marieke Staps has invented a lamp that runs on the natural energy contained in soil.

The Soil Lamp uses a battery made from soil to power an LED bulb.

“The metabolism of biological life produces enough energy to keep an LED lamp burning,” Staps writes on her website.

To stay lit it just needs water adding to the soil from time to time.

Strips of zinc and copper buried in the soil chemically react with the damp soil’s minerals and organisms to produce a constant electric current.

With half the world’s population living in buildings constructed of earth, the Soil Lamp could prove popular in regions with limited access to mains electricity.