Thermodynamic cycles for solar thermal power plants: A review, M. Muñoz, A. Rovira, M. J. Montes, WIREs Energy and Environment, e420, 2021, Online version,  https://doi.org/10.1002/wene.420

Abstract

Solar thermal power plants for electricity production include, at least, twomain systems: the solar field and the power block. Regarding this last one, theparticular thermodynamic cycle layout and the working fluid employed, havea decisive influence in the plant performance. In turn, this selection dependson the solar technology employed. Currently, the steam Rankine cycle is themost widespread and commercially available option, usually coupled to a para-bolic trough solar field. However, other configurations have been implementedin solar thermal plants worldwide. Most of them are based on other solar tech-nologies also coupled to a steam Rankine cycle, although integrated solar com-bined cycles have a significant level of implementation. In the first place, powerblock configurations based on conventional thermodynamic cycles—Rankine,Brayton, and combined Brayton–Rankine—are described. The achievementsand challenges of each proposal are highlighted, for example, the benefitsinvolved in hybrid solar source/fossil fuel plants. In the second place, proposalsof advanced power block configurations are analyzed, standing out: supercriticalCO2Brayton cycles, advanced organic Rankine cycles, and innovative integratedsolar combined cycles. Each of these proposals shows some advantagescompared to the conventional layouts in certain power or source temperatureranges and hence they could be considered attractive options in the mediumterm. At last, a brief review of proposals of solar thermal integration with otherrenewable heat sources is also included.