Power tower concentrated solar plants have the potential to reach temperatures higher than those achievable by a parabolic trough plant. These higher temperatures allow for greater power cycle efficiencies and therefore make power towers an attractive option and a growing topic of research. One common design is to pump water through the tower such that it boils and returns to the power cycle as saturated or superheated vapor. One option to increase power cycle efficiency for a direct steam system is to send the steam exiting the high pressure turbine through a committed reheat receiver section and then through a low pressure turbine.
This paper details a new semi-empirical, first-principles thermal model of a direct steam receiver consisting of dedicated boiler, superheater, and reheater sections. This thermal model — integrated with a regression power cycle model and a heliostat field model in SAM — is used to simulate the performance of a direct steam power tower concentrated solar plant and the analysis results are presented.