Nitrate salt with low melting point as heat transfer and storage fluid simplifies the heat transfer, storage, and exchange processes, and organic Rankine cycle as heat and power conversion system can realize the distributed energy supply. This study experimentally investigated the solar organic Rankine cycle with parabolic trough concentrator using nitrate salt as heat transfer and storage fluid, and the main problems and phenomena during the operation process have been described and analyzed in detail. Experimental results showed that the temperature difference of collector tube changes with direct normal irradiation and lags behind the changes of direct normal irradiation. Molten salt heat storage system can effectively restrain the temperature fluctuation at the collector tube outlet. The abrupt temperature drop at the evaporator inlet was caused by the heat imbalance between R123 and nitrate salt and inappropriate design of the evaporator. The effects of expander inlet pressure and expansion ratio on the ORC electrical power output were obtained at different superheating degrees of the expander inlet. The researches on each component are instructive to the technology of the parabolic trough concentrated solar power generation system with molten salt as heat transfer and storage fluid and provide some guides for the subsequent research.Furthermore, the energy and exergy analyses on overall system were developed, and results indicated the system average efficiency can reach 1.5%.
Novelty statement• Experimental study on parabolic trough concentrated solar ORC system with nitrate salt as heat transfer and storage medium were firstly analyzed.• Single screw expander was firstly applied in a real solar thermal power generation system and showed a stable performance.• Dynamic changes on the temperatures of PTC, molten salt tanks, and ORC were shown, and energy and exergy analyses on overall system were carried on.
In this study, two schemes of solar electrical power generation are designed and compared according to solar collection area minimization. The one comprises the parabolic trough collector, dual-tank of molten salt heat storage, and Organic Rankine cycle. The other consists of photovoltaic cell, polymer electrolyte membrane water electrolyzer, and polymer electrolyte membrane fuel cell. The effects of irradiation value, environmental temperature, and energy storage type on thermodynamic performance were investigated. The results indicated that the solar irradiation value had a more obvious effect on the PV (photovoltaic) cell performance than environmental temperature, and the PTC (parabolic trough concentrator) performance was improved with the increases of solar irradiation value and environmental temperature. The environmental temperature effect was negligible; however, the influence of irradiation value was obvious. Irradiation value had a positive effect on the former system, whereas it demonstrated the opposite for the latter. The latter system had much lower efficiency than the former, due to the low conversion efficiency between hydrogen energy and electrical energy in the polymer electrolyte membrane water electrolyzer and fuel cell. Stated thus, the latter system is appropriate for the power generation system with non-energy storage, and the former system is promising in the power generation system with energy storage.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.