Design and Analysis of Battery Storage Integration in Pico Hydropower System for Low Water Head

Pico hydropower systems offer a practical renewable energy option for rural and offgrid communities, yet their performance is often limited by unstable water flow, especially in lowhead environments. This study investigates how integrating battery storage can improve the reliability and usefulness of lowhead pico hydropower by examining the behavior of two common storage technologies: 12 V 5 Ah lithium-ion and 12 V 5 Ah lead-acid batteries. A complete pico hydropower prototype was designed and constructed with adjustable head levels, turbine-generator coupling, rectification circuitry, and regulated charging components. Experimental trials identified the 5meter head, paired with a 1-inch pipe, 10 mm nozzle, and 0.8 m turbine diameter, as the configuration that produced the most stable electrical output, achieving 33.04 V, 129 RPM, and 1.8 L/s flow rate. Using this optimal setup, each battery type was evaluated under controlled charging conditions to assess its compatibility with the low but continuous power generated by the system. Results show clear performance distinctions: the lithiumion battery required more time to charge (135 minutes), more stable voltage behavior, and higher overall system efficiency (2.5%). Conversely, the lead-acid battery charged quickly but exhibited shorter usable energy duration and lower efficiency, making it less suited for applications requiring sustained output. Overall, the findings demonstrate that lithiumion technology provides a superior storage solution for stabilizing lowhead pico hydropower, enhancing its capability to supply consistent energy despite fluctuations in water availability. This integration is essential in supporting dependable renewable power for remote environments.