Review and characterisation of high-temperature phase change material candidates between 500 C and 700°C.

Latent heat thermal energy storage, by using phase change materials (PCMs), is considered as a promising technology that can be integrated into concentrated solar power (CSP) applications to mitigate the load and electricity supply. Multiple PCMs connected in series has attracted considerable research attention as this configuration has the potential to improve the thermal performance compared to single PCM storage. However, this technology has not yet been deployed in commercial CSP plants. One of the major restrictions is the lack of reliable thermophysical property data for high temperature PCMs. This study gives a broad review of the experimentally verified PCMs with melting temperatures from approximately 500 °C–700 °C, applicable to CSP systems. A further twelve PCM candidates, containing low-cost sodium and/or potassium salts, were identified in this study and their thermophysical properties were experimentally evaluated. It was found that nine of the new candidates can be used as PCMs. • Experimentally verified PCMs with melting points of 500 °C–700 °C were reviewed. • 12 potentially low-cost PCM candidates were identified from the literature. • PCMs were experimentally characterised by using the DSC and TGA. • 9 out of 12 candidates are suitable as PCMs. • The measured weight loss by TGA is in proportion to the estimated vapor pressure. [ABSTRACT FROM AUTHOR]