Scientists looking for a way to provide cheap electricity for people in some of the poorest parts of the world have found a way of running a light bulb off a wood-burning stove. Working with Rida Nuwayhid at the American University in Beirut, Mike Rowe and Gao Min at Cardiff University in Wales have developed a thermocouple device that converts some of the otherwise wasted heat from the stove into a weak electric current.