In this study, the optimal design and operation of an Organic Rankine Cycle (ORC) system driven by solar energy is investigated. A two-tank sensible thermal energy storage system is configured to overcome the intermittency of solar energy. A circulating fluid, also termed as heat transfer fluid (HTF) that connects the solar collector and the ORC system plays a critical role in this system. The mass flowrate of the HTF determines both the temperature of the HTF and the amount of heat absorbed from the solar collector. A simulation-based optimization model is developed in this work. Process simulation of the ORC is performed in Aspen HYSYS, and the mathematical models of the energy storage system and the parabolic trough collector are developed in Matlab. The optimal design of the system including the hot tank temperature, cold tank temperature, mass flowrate of the HTF, and operating conditions of the ORC are determined simultaneously based on the simulation-based optimization framework. The control strategy of the solar collector can be determined as well. The system efficiency of the solar energy driven ORC system is maximized with the proposed optimal operation strategy. With the simulation-based optimization framework, the system efficiency of the recuperative ORC power plant with toluene as the working fluid is increased from 17.9% to 24.8% compared with a previous study in the literature. The recuperative ORC performs much better than the basic ORC. Toluene performs best among all the investigated working fluids ignoring the problem with vacuum condensation. The cycle type (subcritical vs. supercritical) exerts great influence on the system performance. The supercritical ORC can improve the thermal efficiency by 11.3% and the overall system efficiency by 10.8% compared with the subcritical ORC with n-pentane as the working fluid.

在这项研究中，研究了由太阳能驱动的有机朗肯循环 (ORC) 系统的优化设计和运行。配置两罐显热储能系统以克服太阳能的间歇性。连接太阳能集热器和 ORC 系统的循环流体，也称为传热流体 (HTF)，在该系统中起着关键作用。HTF 的质量流量决定了 HTF 的温度和从太阳能收集器吸收的热量。在这项工作中开发了一个基于仿真的优化模型。ORC的过程仿真在Aspen HYSYS中进行，储能系统和抛物槽收集器的数学模型在Matlab中开发。系统优化设计包括热罐温度、冷罐温度、HTF 的质量流量和 ORC 的运行条件是基于基于仿真的优化框架同时确定的。太阳能集热器的控制策略也可以确定。太阳能驱动的 ORC 系统的系统效率通过所提出的优化运行策略最大化。使用基于仿真的优化框架，与之前文献中的研究相比，以甲苯为工质的再生 ORC 电厂的系统效率从 17.9% 提高到 24.8%。康复 ORC 的性能比基本 ORC 好得多。忽略真空冷凝问题，甲苯在所有研究的工作流体中表现最好。循环类型（亚临界与超临界）对系统性能影响很大。