The GOS electrical power system has been tailored for the needs of CubeSats. It includes an autonomous lithium-ion battery charging regulator, as well as a power distribution unit for an efficient management of the satellite’s resources. The EPS is powered by up to six solar arrays. Best performance is achieved in combination with GOS solar arrays and the battery packs. The system is fully compatible with the CubeSat Kit specification. If no special requirements concerning computing power or redundancy are made, the GOS EPS can substitute an OBC and help to reduce the overall mission costs.