Validation of a thermal storage model in the Virtual Solar Field software using operating data from the Évora Molten Salt Platform

Abstract

Parabolic trough power plants use solar radiation to heat a heat transfer fluid (HTF) up to the design temperature. However, solar radiation often causes transient conditions in the solar field. For example, the solar field, which has cooled down overnight, has to be restarted every morning to bring the outlet temperature to the set point. Cloud passages can influence the spatial irradiation, which can lead to temperature fluctuations or different focusing of the collectors. Dynamic simulation tools that can cover these transient scenarios are used to develop operating strategies for the solar field. Such a simulation program, called Virtual Solar Field (VSF) [1], [2], has been developed at DLR. This simulation program makes it possible to carry out such simulations using spatially resolved irradiation data. The extension of the tool to include the thermal storage allows the representation and simulation of the entire HTF cycle. The aim of this work is to validate the thermal storage in VSF using real operating data from the Évora Molten Salt Platform (EMSP) [3].