Experimental investigation of the solar latent heat thermal energy storage system integrated with salt hydrate phase-change materials

To achieve rational utilization of renewable energy sources, a solar latent heat thermal energy storage system for hot water application was developed in this study. The feasibility of the salt hydrates using in the solar heating was assessed and the comparative experimental investigation was conducted under various operating conditions. It shows that the higher flow rate and radiation accelerate the melting process of the phase-change material. The time taken for the storage medium to reach phase transition was reduced by approximately 48.9%; meanwhile, the collector efficiency was enhanced by approximately 10.2% as the flow rate increased from 10 g/s to 30 g/s. The accumulated charging energy increased by approximately 10.9% when the radiation increased from 850 W/m² to 920 W/m², resulting in a prolonged heat release process. The test results suggest the promising potential of the salt hydrates for the solar water heating applications.