Temperature-based optical design, optimization and economics of solar polar-field central receiver systems with an optional compound parabolic concentrator

Energetic and economic characteristics are studied for solar central receiver systems consisting of a polar heliostat field, a tower, a single-aperture cavity receiver, and an optional compound parabolic concentrator (CPC). System characterization and optimization are performed with a numerical model combining an in-house developed Monte-Carlo ray-tracing optical model, a simplified receiver heat transfer model, and a cost model based on the System Advisor Model (SAM). Based on the model, the effects of receiver temperature on the optical configuration of cost-optimal systems are elucidated, along with the benefits of using a CPC for improved energetic and economic performance. Under the assumptions made in this study, it is found that the overall minimum levelized cost of exergy is obtained by a non-CPC system with a receiver operated at approximately 900 K. A CPC benefits both the energetic and economic performance of systems only at elevated temperatures. The working temperature thresholds at which the energetic and economic performance benefit from the addition of a CPC are identified as 900 K and 1200 K, respectively. The general formulation of the model and broad range of values of the investigated parameters provide a universal predictive capability for studying techno-economic performance of concentrating solar thermal systems.