Minimizing water consumption in concentrating solar power (CSP) plants through integrated organic Rankine cycle waste heat recovery

Concentrating solar power (CSP) installations for large-scale power generation face challenges related to the low yield and high-water consumption to ensure the cooling process, which make them less competitive compared to conventional thermal power plant. To solve these two issues, a reference CSP plant with an output of 19.9 MW is retrofitted by integrating a waste heat recovery system (WHRS) based on an organic Rankine cycle (ORC) to raise the dispatchability of the installation and reduce both water and power consumption in its cooling tower. The obtained results show that by integrating this new solution, the new plant achieved a 15.30% increase in generated electricity, a 15.13% improvement in global efficiency, and 15.35% increase in capacity factor, while reducing wasted heat by 16.90%, water consumption by 23.37%, and cooling power demand by 24.63% compared to the Gemasolar reference plant. Furthermore, this novel solution enhances the long-term sustainability of CSP plants, as evidenced by a reduction in water consumption of nearly 1.04 Mm3 at the Gemasolar plant over its 30 years old-life cycle.