The development of advanced power grids is necessary to expand mankind’s habitat into previously uninhabitable regions, such as deep space or sea. Wired electrical or gas pipeline networks have been conventionally used to construct effective power grids. However, the use of metal wires or pipes in extreme environments is considered problematic. Therefore, wireless power grids are considered to be useful and technologically advanced alternatives for applications in deep space or sea. In this report, we discuss an optical wireless power grid for an artificial space satellite network that uses a high-power laser and high-efficiency optoelectric (OE) converter technologies. We estimate a high-energy transport efficiency of 8.5 % between the power units in two artificial satellites that utilize a free-space optical connection based on a high-power laser and an OE converter. Based on these considerations, we expect that optical wireless power grids that utilize free-space optical networks will emerge as a cutting-edge technology to achieve power interchange between a large number of small space satellites.