Innovative 3D-Shaped Structures as Volumetric Absorbers

Abstract

As proven by the continuous operation of the Solar Tower Juelich, central receiver power plants with open volumetric receivers are a valid alternative to other receiver types. Evolving new manufacturing techniques will allow to advance the technology further by improving its core component, the porous absorber structures. Using ceramic 3D screen printing, the new StepRec absorber design is fabricated out of siliconized silicon carbide and is presented along with the second new structure, the Emitec absorber made of very thin metal sheets. Based on experiments in the high-flux solar simulator Synlight, the thermal efficiency of both new designs is derived for reduced-size absorber probes. The new structures outperform the state-of-the-art HiTRec absorber with efficiencies above ninety percent at air temperatures of 650°C. Full-size absorber modules have been tested under real irradiation conditions at the research platform of the Solar Tower Juelich. The thermal efficiencies of the full modules will be quantified with further experiments in the Synlight facility in the near future.