State of the Art of Performance Evaluation Methods for Concentrating Solar Collectors

For the development and establishment of concentrating solar thermal collectors a reliable and comparable performance testing and evaluation is of great importance. To ensure a consistent performance testing in the area of low-temperature collectors a widely accepted and commonly used testing standard (ISO 9806:2013) is already available 1. In contrast to this, the standard ISO 9806:2013 has not completely penetrated the testing sector for concentrating collectors yet. The reasons for this are diverse. Among them are technical limitations in the established methods which increase the effort of applying the methods to an inappropriate extent. Furthermore some specific characteristics of concentrating collectors are not represented by the given theoretical models (e.g. two-dimensional incidence angle modifier including the effect of row end losses and cleanliness of mirrors during testing). On that account a detailed literature review has been performed on published testing procedures and evaluation methodologies, which will be presented in the first section. As a complement a survey has been conducted among ten participants of relevant industry and research institutions within the European project STAGE-STE (Work package 11 - Linear focusing STE technologies), giving indications on the up-to-date state of the art of currently implemented testing procedures.