Solar Heat Storage and Application

Thermochemical heat storage materials offer high-energy storage densities and clean means of long-term solar energy storage. The aim of the study is to assess the potential heat storage efficiency of salt hydrates, based on sufficient hydration/dehydration performance, water sorption, and cycliability. Pure MgSO4-7H2O, ZnSO4-7H2O, and FeSO4-7H2O and their salt-salt and salt-zeolite were evaluate based on preselected criteria. The booming progress of ZnSO4-7H2O illustrates that likewise MgSO4-7H2O, it is also the potential candidate and can be used in thermochemical heat storage devices. Composite of ZnSO4/13X-zeolite showed the highest water sorption (0.26 g/g) at 75% relative humidity under 45 C air temperature, which is double than of pure ZnSO4-7H2O. MgSO4/ZnSO4 (MZ9) composite was prepared and characterized for their long-term heat storage application. The hydration behavior of MZ9 reveals an ideal thermochemical heat storage candidate for thermal storage devices.