Exergetic Analysis and Performance Optimization of a Hybrid Solar Tower-Parabolic Trough Power Plant

The study demonstrates that proper temperature matching through process integration significantly reduces irreversibilities and enhances second-law efficiency. These findings provide valuable guidelines for the design and optimization of future high-performance hybrid CSP plants. The combination of solar tower and parabolic trough technologies may have great potential for enhancing the overall performance of concentrated solar power (CSP) plants. A detailed exergetic analysis of a hybrid solar tower-parabolic trough power plant is presented in this paper, in which a medium-temperature heat from the PTP field is used in the Rankine cycle of a high temperature solar tower plant. A validated one-dimensional thermal model of the parabolic trough collector was coupled with the solar tower model developed by Spelling (2008). The amount of exergy destroyed in every component was calculated, and the exergetic efficiency was calculated over a wide capacity range for the troughs (5-2000 MWth). The exergetic efficiency is improved up to 38% for the hybrid configuration over the standalone tower plant; the optimum trough size is between 800 MWth to 1200 MWth. The significant exergy destruction (EDE) in the receivers of the solar systems (solar receivers and heat exchangers) indicates potential opportunities for further optimization. The study shows that by using process integration, irreversibilities are kept to a minimum, and second-law efficiency is improved if the process is integrated properly. The results obtained are a useful guideline for the design and optimization of future high-performance hybrid CSP plants.