Quantifying optical loss factors of small linear concentrating collectors for process heat application

Concentrating solar collectors such as small Parabolic Troughs and Linear Fresnel Collectors are well suited to generate industrial process heat in the medium temperature range between 150 °C and 300 °C. For detailed optical yield simulations and performance evaluation of process heat applications state of the art assumptions and model simplifications (e.g. models for incidence angle modifier and end losses) are analyzed and compared to exact ray tracing results. An approach towards an optical model and exemplary values for geometrical optical losses and materials are presented. Optical loss factors are quantified and a corrective function is proposed for end loss modeling. The main focus of the paper lies on the analysis of Linear Fresnel Collectors.