Cost performance of encapsulated phase change material-based thermal energy storage systems

Abstract

Abstract The cost of thermal storage is crucial to the economic viability of concentrated solar power plants. The aim of this study was to investigate ways to reduce the cost of latent heat thermal energy storage systems, in particular encapsulated phase change material technology. A design approach based on the heat transfer modelling, with consideration of the cut-off temperatures, was established. The model was solved using a control-volume methodology with an implicit scheme. Various configurations were investigated, considering a 100-MW power plant with 6 hours of backup capacity. The results indicate that there is a possibility to significantly reduce the capacity cost to about $9/kWht when the internal insulation of the storage tank along with a low-cost ceramic shell and chloride-based salts are used.