Thermochemical storage modelling and optimization within multi-energy systems

The development of renewable energy technologies is nowadays strictly connected to the capability of realising efficient and economically competitive storage systems. The possibility of storing energy allows the optimal exploitation of intermittent energy sources, reducing overall energy consumption for the energy demand satisfaction and increasing the operating flexibility. Within this framework, thermochemical storage is becoming a hot topic in the field of thermal storage, due to higher theorical energy density achievable with respect to sensible and latent heat storage systems. At the state of art, only small prototypes exist and the main part of the research activity is still at the material level, which is problematic due to chemical instability issues of the involved materials. This work aims to provide some guidelines for the further development of the technology by bridging the material level of analysis to the system level, modelling salt hydrates based thermochemical storage systems within multi-energy systems (MES) optimization problems. Three main case studies are simulated, given by different combinations of energy technologies, aiming to the satisfaction of a single household thermal and electric demands in Utrecht, in The Netherlands. Results show that the main termochemical storage system parameters variation, i.e. charging/discharging efficiency, thermal losses coefficient and material cost, plays a predominant role in affecting the system performances.