In Situ Characterization of Thermal Collectors in Field Installations

Reliable and significant determination of the collector performance in field installations is necessary for a number of reasons, such as commissioning tests or product certification. The standard measurement methods from ISO 9806 are subject to numerous restrictions and only partially applicable to solar field installations. In a current project, different solar thermal plants are being monitored in order to examine the adaptability of standard procedures and measurement equipment to the requirements of in situ testing in comparison with a non-standard dynamic testing approach. Within the scope of the examinations is the comparability of field and laboratory results with respect to different evaluation methods, measurement equipment, system boundaries and process conditions. A new software tool to handle and visualize large data volumes was implemented as well as an advanced analysis procedure of parameter quality via alternative confidence interval computation. This is crucial to evaluate the uncertainties associated with larger field testing.