Development of a Hybridized Solar-Hydro Autonomous Power Generating System

Abstract

Reliable electricity supply in remote and off-grid communities is limited by the intermittency of single renewable sources, particularly solar-only systems that depend on daylight availability. This study presents the design, fabrication, and performance evaluation of a hybridized solar–hydro autonomous power generating system developed to provide stable, low-cost, and continuous energy for small office and residential applications. A load demand of 765 Wh/day was established and used to size the major components, including two 150 W photovoltaic panels, a 12 V 100 Ah lithium-ion battery, a Kaplan-type micro-hydro turbine, a DC water-circulation pump, and a 300 W pure-sine inverter. The system was designed to generate approximately 1224 Wh/day from the solar subsystem to account for inefficiencies, while the turbine was designed for an expected output of 128 W at a head of 1.5 m. Performance testing was conducted for seven consecutive days under real operating conditions. Results showed that the solar subsystem produced an average of 1180 Wh/day, representing 96% of the design target, while the battery operated with a usable efficiency of 92%. The hydro turbine delivered an average of 85 W at 82% efficiency, primarily limited by practical head conditions. The combined system consistently exceeded the daily load, achieving 100% uptime and an overall energy efficiency of 87.5%. The findings demonstrate that hybridization significantly improves reliability by compensating for solar variability and maintaining uninterrupted power delivery. Further enhancements in turbine design and automated control are recommended to improve long-term performance and scalability.