The rocket stove was first designed by Dr Larry Winiarski in 1980. It is a clever design for cooking, which greatly improves the combustion efficiency of the fire and significantly reduces smoke. The benefits are monumental, with firewood reduced by a massive two thirds, whilst smoke is largely eliminated - a major health advantage for Africans who generally cook inside their homes. The indirect benefits are also important. Rocket stoves are more efficient meaning that women spend less time each day in collecting wood and cooking food, and young children are no longer exposed to the dangers of an open fire. Perhaps one of the best features of the rocket stoves is that they are free. Built from clay and grass, with the right training, construction of a rocket stove can be undertaken by any household.