In Gatina slums Celina Apondo has to spend almost 3500 Ksh a month on charcoal to cook. Her old cooking stove uses a lot of charcoal. It also takes a long time for the food to get ready, more than 1,5 hours. More than sixty percent of Kenyans use charcoal or wood as main source of fuel. Penina Nabaye Okumu now uses a new stove which uses less charcoal, cooks faster and also lasts longer. Your reporter is Peris Wairimu.