Preliminary exergy analysis of ASTEP system

The ASTEP concept was proposed within the European Project with the same name (Application of Solar Thermal Energy to Processes). It consists in the integration of a rotary Fresnel collector and a Phase Change Material (PCM) Thermal Energy Storage (TES) connected in series with the collector, to demonstrate the viability to cover the energy demands of industry processes with solar thermal technologies. The concept will be tested in two industrial sites with different demands and meteorology. The maximum working temperature will be 240ºC, and the heat thermal fluid is Therminol 55®. The demand studied in the first case (Mandrekas, Greece) is a boiler producing steam at 175ºC and two chillers to cool water at -5ºC. This work aims to assess the exergy analysis of the concept.

Majority exergy losses are located in the solar receiver, followed a long way behind by the salt heat exchanger, and in the same order of magnitude, boiler and pumps/valves losses.