Limitations of size and mass obstruct small satellites to have energy storage and generation freely. However, any satellite that brings SAR (synthetic aperture radar) payload requires much bigger energy storage compared to, for example, one that brings an optical payload for remote sensing mission. This paper addresses an energy balance analysis for microsatellite such that the remote sensing mission using SAR payload is successfully run. A specific LEO orbit, attitude of satellite, and position of solar panel are taken as a constraint in the simulation to obtain data used in potential solar power generated calculation. Potential solar power generated with specific dimension of solar panel is calculated by considering three solstice and equinox. In addition, the shadow that covers solar panel due to part of satellite is also considered. Energy balance analysis compares between potential solar energy generated by solar panel and energy consumption such that the SAR mission is achieved.