It is essential for lighting, heating and cooking, as well as for education, modern health treatment and productive activities. Yet 1.6 billion people lack such access, and more than half of all people living in developing countries rely on the combustion of traditional biomass (e.g. wood) to meet their basic energy needs for cooking and heating. Lack of access to modern energy sources is both the result and the cause of poverty, as it exacerbates and perpetuates poverty.