Performance Evaluation of the 200-kWth HiTRec-II Open Volumetric Air Receiver
The High Temperature Receiver (HitTRec) consists of a modular ceramic absorber, a supporting structure and an air-return system. It has been designed to prevent possible flow instability at 700-800°C average outlet air temperature with atmospheric pressure. The HiTRec-II prototype was developed to solve the structural problems of the first prototype (HiTRec-I). Testing in the Plataforma Solar de Almerı´a (PSA) test bed lasted from November 2000 through May 2001, accumulating 150 test hours under concentrated sun. Results demonstrated the durability of the modified stainless-steel structure. Inlet aperture flux was up to 900kW/m2 and average outlet air temperatures of up to 840°C with peak outlet air temperatures of up to 950°C. Thermal efficiency under steady-state conditions was 76±7% at 700°C, nominal conditions for a PHOEBUS-type volumetric receiver. Other performance characteristics were also evaluated (e.g., Air Return Ratio of 46% and characteristic receiver response time of 70 s).