Water saving potential of CSP-PV hybrid plants

Abstract

Within the consideration of the potential benefits of a CSP-PV hybrid over a CSP stand-alone plant, the usage of water has been analyzed. Specifically at arid locations, which are typically preferred for CSP due to the high irradiance, water is a scarce resource, and options to save water are worth consideration. The conservation of water is an important factor in the further development of CSP sites in these areas. In an effort to identify water saving potential of CSP-PV hybrid plants compared with CSP plants, a case study has been performed on the basis of a fictive project in an arid region with an air-cooled condenser (ACC) cooling system. Besides the required make-up water for the CSP steam cycle, the water consumption for cleaning the solar field has been identified as one of the main driver for the total water consumption and has been analyzed in more detail. Provided that PV performance is less affected by soiling when compared to CSP, less cleaning cycles are required for PV modules. The results of this case study show that a CSP-PV hybrid has the potential to reduce the total water consumption of a plant by approximately 43% compared with a CSP only plant configuration. Moreover, the results indicate that the water consumption can further be reduced by almost 60% if dry cleaning is used for the PV modules.