Long-term performance of latent heat thermal energy storage using supercooling

Performance of a long-term latent heat thermal energy storage unit which uses supercooling was experimentally investigated. The volume of the storage tank is 53 l and the tank has 31 capsules of phase change material (PCM); dsodium hydrogenphosphate dodecahydrate. The total heat of fusion of the PCM is 9.1 MJ. The result of the experiments shows that the storage unit can control the nucleation of the supercooled PCM after 204 days from the beginning of the melting operation. From the result of the storage operation between 22 degrees C and 66 degrees C, the sensible eat of the unit was released to the room and lost, but the itent heat remained in the tank and 49 % of the initial stored heat was recovered by the nucleation operation.