High Temperature solar receicver with ceramic materials

Abstract

Ceramic materials enable the development and design of advanced solar receivers for high working temperatures (> 600°C). Main advantage is that ceramic materials show very low creeping at high temperatures and the low thermal expansion coefficients, leading to the higher mechanical strength in comparison to metallic materials. In addition, these materials are highly resistant against corrosion or abrasion caused by heat transfer medias, such as solar salt, liquid metal or abrasive granular solids. Currently, various receiver concepts for high temperature solar receivers with ceramic materials are under development at DLR. In open or closed type volumetric receivers a porous ceramic absorber is irradiated by the concentrated solar radiation. In this technology the heat is transferred to the fluid by taking advantage of the large surface area. Furthermore the heat must not be conducted through a wall as the absorbing surface is also the transfer surface. Another example are ceramic plate receivers, which can be used to transfer the solar radiation energy to pressurized air, which is flowing through channels inside ceramic plate modules. Finally, in particle receivers solid granular ceramic particles are absorber, heat transfer and storage media. Special conditions, such as the inhomogeneous solar radiation or the thermo-hydraulic boundaries from the power block, make the development of these solar receivers challenging. In this paper, the authors present an overview of the workflow and tools for receiver layout and receiver optimization for the different receiver types.