In most countries of equatorial Africa, it is difficult to satisfy power demand all year long by hydro sources alone. In some remote areas, where this is the case, a judicious combination of other renewable sources to form a hybrid system can help solve rural electrification problems. One of these combinations is the use of PV together with a diesel and batteries. We highlight the use of an optimization model to size such a system in a village in Cameroon. (C) 2009 Elsevier Ltd. All rights reserved.