Performance assessment of a secondary concentrator for solar tower external receivers

In the EU-project RAISELIFE, a secondary concentrator for Solar Tower systems has been developed conceptually, which is discussed techno-economically herein. Based on a detailed three-level simulation methodology (optical assessment of radiation distribution on receiver surfaces, thermal FEM-simulation of receiver efficiency and transient system simulation), an annual performance assessment of the secondary concentrator by means of a reference system incorporating a receiver with a thermal rating of 600 MW is presented, including a breakdown of the different loss contributions. The annual electrical yield for the secondary setup is increased by 1.57% compared to the reference system, with the potential for further boosts. Regarding material and component costs, an integration of this secondary design could decrease the receiver costs by up to 6.1%.