The usual way for solar water heaters to store heat is by using sensible heat, increasing the temperature of water and an antifreeze mixture in the water storage. Using PCMs is a new way and it has a lot of different benefits.
Solar water heater performance was investigated by using the latent heat of a PCM and the sensible heat of water in a hot water storage and they studied on how to improve its performance from the viewpoint of energy and exergy.
In this method, a kind of PCM with special thermodynamic attributes was used as a PCM inside spherical capsules in the storage tank.
Experiments occurred in three different radiation conditions of low, medium and high, and the results showing the most improvement in storing energy were the ones conducted in the high condition by 39%. In the exergy storing, the most improvement was found in the medium condition by 17%.