High-temperature two-layer integrated receiver storage for concentrating solar power systems

An integrated receiver storage for a beam-down concentrating solar power (CSP) plant enables simplifying the system layout and reducing the costs. Here a two-layer integrated receiver storage (TLIRS) system design is proposed consisting of a cavity receiver and a two-layer packed-bed storage. The first layer is a porous ceramic and the second one is rocks. To enable performance optimization of the system, models for cavity radiation, two-phase transient heat transfer and local thermal nonequilibrium were derived and validated. The thermal performance of the TLIRS system was assessed and characterized by the absorbing, charging, discharging and overall efficiencies and by the solar-to-exergy conversion ratio. The results indicate that the porous ceramic layer significantly enhances the absorption of solar irradiance and thus improves the thermal efficiencies. For CSP applications, the TLIRS system potentially achieves high thermal performance in repetitive charging and discharging cycles.