Paper Title
Parametric Optimization of Piston-Based Gravity Energy Storage for Photovoltaic Power Systems

Abstract
The increasing global reliance on renewable energy has driven the need for advanced energy storage technologies to mitigate the intermittent and fluctuating nature of solar and wind resources. The renewable energy sources are integrated with piston-based gravity energy storage to be cost-effective for large-scale applications. Key design variables, including container height, hp/Hc ratio, material density, and return pipe diameter, were analysed through design and the calculation modelling of the proposed system. The results reveal that the configuration with a container height of 79 m and reinforced concrete as the construction material achieved a system efficiency of 81 % and reduced the power loss by 6% compared to other designs (cement, container height of 82 m) in power performance. Increasing the hp/Hc ratio was found to raise power loss, whereas enlarging the return pipe diameter significantly reduced hydraulic losses. The optimized configuration demonstrates improved system performance and structural stability, confirming the suitability of reinforced concrete as an economical and durable material for GES systems. This study provides a validated modelling framework and offers key design insights for next-generation gravity-based energy storage. Keywords - Gravity Energy Storage, Piston Based Storage, Renewable Energy Integration, Hydraulic Losses, MATLAB/Simulink.