Hybrid Solar Cooling Using Photovoltaic Panels and Graphene-Enhanced Phase Change Material Thermal Storage

Abstract A hybrid solar cooling system is developed to deliver continuous cooling for a 30 m2 building with a 5 kW cooling load, utilizing both solar photovoltaic (PV) and thermal energy. During the day, an adsorption chiller operates using PV electricity, while at night, an absorption chiller is powered by stored thermal energy. Heat is collected via a flat plate collector and stored in paraffin wax phase change material enhanced with graphene, which improves thermal stability and storage capacity. This enables a high coefficient of performance of 0.95 for both chillers. Simulated under tropical climate conditions, the system consistently meets cooling demands with 90% overall efficiency. Economic analysis reveals a payback period of 14.2 years and a levelized cost of energy at RM0.14/kWh, highlighting its cost-effectiveness. The system presents a sustainable, energy-efficient alternative for cooling in tropical regions, reducing dependence on conventional energy sources and supporting long-term energy savings.