Modeling of a thermal energy storage system coupled with combined heat and power generation for the heating requirements of a University Campus

The optimum efficiency in the exploitation of a given energy resource in the cogeneration of electrical power and thermal energy requires the simultaneity of the electrical and thermal demands. Moreover, when the thermal demand is strongly time-varying or even discontinuous, the use of a thermal energy storage coupled with the cogeneration engine provides an attractive solution by allowing the production of dispatchable electrical power while more profitably exploiting the thermal energy available from the prime mover. The excess cogenerated heat can in fact be stored and then dispatched later when it is required by the thermal load. In the present work the simulation of a cogeneration facility coupled with a thermal energy storage system is considered. In order to assess and quantify the validity of such a solution, a practical case study is analysed: the model is applied to match the heating requirement of the buildings belonging to University of Parma Campus. The results of the energetic and economical analysis confirm the effectiveness of this solution strategy, based on the thermal energy storage system, by providing important guidelines in the choice of its optimal size.