Methods and instruments under development: New methods and instruments for performance and durability assessment

Abstract

Two basci approaches exist to derive receiver solar absorptance. The first apporach is to measure an enthalpy difference of a medium inside the receiver and the receiver itself by irradiating it with lamps or the sun. The second Approach is to meaure directly the reflectance of glass envelope and absorptance of the selective coating. While the first Approach ususally includesthe whole Receiver assembly, whish is important for product qualification, the second Approach is a more direct measurement of the properties of the Receiver which have a Major influence on reciever performance. The indoor OptiRec and ElliRec test benches, the outdoor two-axis tracking SolarRec or KONTAS test benches or a typical one.axis tracking parabolic trough can be used to measure the temperature increase of the fluid flow inside the receivers.