Direct Thermal Comparison of New Generation SiC Solar Absorbers

A new generation of volumetric absorbers has been developed to improve both the mechanical robustness of SiC ceramic structures and the thermal behaviour of the new geometric designs. Within the NEXTOWER project, two new absorber designs have been developed for these purposes, one developed to improve mechanical performance and durability, and the other aimed at improving the thermal performance of the absorbers through a new gradual porosity design. Both designs have been tested, alongside of current state-of-the-art ceramic absorbers, under real concentrated solar radiation in the SolAir3000 receiver of the Plataforma Solar de Almería. The results show that the gradual porosity design is a promising way to significantly improve the thermal efficiency of volumetric SiC absorbers. At the same time, the new manufacturing processes show a significant improvement in the mechanical strength and durability of the new generation designs.