Solar polygeneration for electricity production and desalination: Case studies in Venezuela and northern Chile

In this study, a polygeneration system incorporating concentrating solar power (CSP) integrated with a desalination plant is investigated. Parabolic trough collectors (PTC) and multi-effect distillation (MED) technologies are considered, and a transient system model has been simulated using the TRNSYS software. Two alternative desalination integration options and two potential locations in Venezuela and Chile with electricity and freshwater supply problems were selected and studied. Chile has also set a 20% target for non-conventional renewable energy production by 2025; therefore a polygeneration system coupled with desalinization plant is aligned with the needs of both countries. The results show that the CSP polygeneration plant can provide electricity and freshwater to more than 85,000 inhabitants at a reasonable cost; however the costs and feasibility depend principally on the irradiation, the location of plant with respect to the sea, and the specific conditions of each country. With the projected costs expected to decrease, it could be feasible to develop a CSP polygeneration plant in either country. For the Chilean case, LEC and LWC can be reduced to competitive prices if the initial PTC investment cost could be reduced by 15% for the Chilean case, and by 25% for the Venezuelan case.