Initial Analysis on the Novel Spiky Central Receiver Air Pre-heater (SCRAP) Pressurized Air Receiver

Abstract

Abstract A combined cycle (CC) concentrating solar power (CSP) plant provides significant potential to achieve an efficiency increase and an electricity cost reduction compared to current single-cycle plants. A CC CSP system requires a receiver technology capable of effectively transferring heat from concentrated solar irradiation to a pressurized air stream in a gas turbine. The small number of pressurized air receivers demonstrated to date have practical limitations, when operating at high temperatures and pressures. As yet, a robust, scalable and efficient system has to be developed and commercialized. A novel receiver system, the Spiky Central Receiver Air Pre-heater (SCRAP) concept has been proposed to comply with these requirements. The SCRAP system is conceived as a solution for an efficient and robust pressurized air receiver that could be implemented in CC CSP concepts or standalone solar Brayton cycles without a bottoming Rankine cycle. The presented work forms part of an initial analysis intended to provide an answer to whether the proposed SCRAP concept can effectively absorb the concentrated solar radiation and transfer the captured heat into a pressurized air stream in a robust and cost-effective manner, while maintaining an acceptable pressure-drop. A ray-tracing study was executed to identify the sensitivity of the SCRAP receiver to optical plant parameters, such as the heliostat size. A one-dimensional heat transfer analysis was initiated to develop initial understanding of the thermal system behavior and generate a tool for rapid geometry optimization.