Application of liquid metals for solar energy systems

Karlsruhe Institute of Technology (KIT), 76131, Karlsruhe, Germany

Abstract

Liquid metals have excellent properties to be used as heat transport fluids due to the high thermal conductivity and their wide applicable temperature range. The latter opens the gate utilizing more efficient power conversion options beyond the limitations of current thermal solar energy systems. By utilizing them as thermal storage medium, an improved coupling of state-of-the art power conversion systems (PCS) to solar plants seems promising. To avoid adverse effects of highly reactive fluid a compact design is envisaged, which fits best to concentrating solar power (CSP). In this context a solar storage system is proposed and will be qualified for fast reaction to compensate solar flux fluctuations and to optimize PCS. The paper will provide an outlook based on a concept study for a 100 MWth plant with a comparison to existing thermal solar plants. The vision also includes the capability for base load applications, including a day-wide storage system. Combining both systems, a fast response of the plant to compensate short term fluctuations from other renewable sources or from energy consumption is feasible.