Performance of direct steam generator solar receiver: laboratory vs real plant

The Levelized Cost Of Energy (LCOE) of a Concentrated Solar Power (CSP) plant strongly depends on the costs and efficiency of the solar field. A three-fold configuration has to be considered to optimize the chosen technology: Thermal Energy Storage (TES), Heat Transfer Fluid (HTF) and the concentration system technology. Direct Steam Generation (DSG) represents a realistic alternative to the existing HTF solutions (molten salt or diathermic oil) as it uses water to feed the plant and get steam to be potentially directly injected in the steam turbine. When applied to parabolic trough, the whole plant is undergoing a sequence of technological new problems [1] presently under further investigation within the CSP community, as for instance dedicated innovative thermal energy storage systems [2]; the equilibrium between costs and efficiency is yet to have been exhaustively defined and leaves therefore large room for investigation and research. This paper will be dealing with the dedicated efforts provided by Archimede Solar Energy to its DSG solar receiver (HCEDSG-12), presenting the solution chosen to get rid of the extremely hard operating conditions. Results obtained from half a year-long real plant investigation will be discussed, demonstrating the technical feasibility of this intriguing technology. (C) 2015 The Authors. Published by Elsevier Ltd.