Exergy analysis of a multi–tank thermal storage system for solar heating applications
This paper presents the results of an experimental study on the stored exergy of a stratified multi–tank system when subjected to various charge and discharge strategies. Tests were performed over 8–h and 48–h test periods, for constant temperature charging, variable input power charging, constant volume hourly draws and variable volume hourly draws. For each set of test parameters, three different charge and discharge configurations were evaluated. Results showed that for constant charge and discharge conditions, the parallel charge and parallel discharge configuration achieved the highest stored exergy value at the end of the test period. Under variable charge and discharge conditions, the series charge and series discharge configuration resulted in higher stored exergy values. This work was supported by computer modelling conducted in the TRNSYS simulation environment.
Keywords: exergy analysis, solar heating, TES, thermal energy storage, sensible storage, multi–tank systems, natural convection, heat exchangers, draw profiles, modelling, simulation, solar energy, solar power