Linear Fresnel collector mirrors - Measured systematic surface errors and their impact on the focal line

Abstract

Objective of this article is to show and discuss the shape accuracy of solar reflector panels for linear Fresnel collectors. Systematic shape deviations due to torsion or orientation errors are responsible for severe optical losses and underperformance. This is why this article investigates systematic surface deviations beyond the standard quality parameters like SDx and FDy. We discuss typical characteristics of linear Fresnel collector reflector panels. Our measurement results show local surface slope deviations measured by deflectometry. In the second part of this study, the effect of systematic surface slope deviations is analyzed by use of a parametric model. We apply the model to detect systematic production errors, investigate optical losses and the impact on the focal line with ray tracing.