The use of renewable energy sources has great potential for generating electricity. This potential can be realized through the use of hybrid power systems. The development of this hybrid power plant features two power sources: Picohydro and solar power generation. Solar Power Plants (PLTS) and Picohydro Power Plants (PLTPH) are the most suitable renewable energy developments for Indonesia due to its highly potential tropical climate. The aim of this research is to develop a control system for a hybrid solar and picohydro power plant by creating a relay switch control system to connect and disconnect one power source to another. After the design was implemented, it was found that the device was capable of backing up electricity. When the picohydro system dims or shuts down, the PLTS battery will back it up, and vice versa.