In the fight against climate change it is of tremendous importance to reduce greenhouse gas emissions from electricity generation and industrial processes. The new solar thermal technology CentRec® can contribute to this goal by providing cheap solar heat that can be easily stored.
Using ceramic particles in solar tower systems allows higher temperatures at low cost
Current solar tower technology uses molten salt as heat transfer and storage medium. An alternative approach is based on small ceramic particles, e. g. bauxite spheres with about 1 mm diameter. The use of such particles in solar thermal power plants with thermal storage opens up new degrees of freedom for cost reductions. The particles can be used at temperatures up to 1,000°C and contrary to molten salts do not require precautions against freezing. Also, they are cheap and do not pose any harm for the environment. Furthermore, due to the high maximum temperature, new applications in solar process heat applications are feasible.
A first prototype of a solar receiver using ceramic particles has been successfully developed by DLR and tested under solar conditions at the Juelich Solar Power Tower. During irradiation, the temperature sensors at the outlet of the receiver measured up to 965°C.
Acknoledgements
This work was supported by DLR's Department for Technology Marketing, the DLR Energy Programme Directorate (grant no. LRV 16/113) and the Helmholtz Validation Fund (HVF) of the Helmholtz Association (grant no. HVF-0028).