The Nias Islands still face electricity shortages, particularly in remote areas that are not yet fully connected to the PLN grid, despite having significant potential for solar and micro-hydro energy. This study aims to design a hybrid power generation system combining Solar Power Plants (PLTS) and Micro-Hydro Power Plants (PLTMH) to support sustainable energy supply. The research employed a quantitative approach through simulations using HOMER Pro software, utilizing solar radiation data, river discharge, and community electricity load profiles. The simulation results indicate an optimal configuration with a 6 MW PLTS and a 1 MW PLTMH, capable of producing 7,326,788 kWh of electricity per year. From an economic perspective, Scenario I (with PLTD) yields a Net Present Cost (NPC) of Rp457.28 billion and a Levelized Cost of Energy (LCOE) of Rp40,620.39/kWh, whereas Scenario II (without PLTD) results in an NPC of Rp150.23 billion and an LCOE of Rp13,345.11/kWh. These findings confirm that Scenario II is more efficient, cost-effective, and environmentally friendly, with a renewable energy penetration of 100%.