To quicken the process for high global warming potential (GWP) working fluid replacement for organic Rankine cycle (ORC) systems, a thermo-economic evaluation of low GWP fluid R1233zd(E) as an R245fa alternative has been performed in comparison with other natural fluids n-Pentane, Isopentane, and Isobutane for geothermal applications. The heat source water mass flow rate remains constant and 5 K pinch point is set for both evaporator side and condenser side. All working fluids have a close net thermal efficiency within 2%. Increasing the heat source from 120 °C to 160 °C gives a more than 20% efficiency rise. The low critical temperature of Isobutane limits its application for 160 °C heat source. R1233zd(E) displays a close mass flow rate (within 2%) from R245fa and others exhibit more than 40% flow rate reduction. The component level performance has also been investigated in this study. All alternatives exhibit a lower evaporator side (evaporator and preheater) heat transfer area than baseline R245fa, and a slightly higher condenser side (condenser and desuperheater) heat transfer area. For turbine performance, R245fa displays the highest volume flow ratio, indicating a significant change of the rotor blade height should be made between the inlet and outlet point for the expansion process. R1233zd(E) displays ∼10% increase for turbine size parameter from baseline, n-Pentane shows ∼22% rise, Isopentane exhibits ∼11% rise, while Isobutane presents 32% decrease, respectively. In general, R1233zd(E) only exhibits ∼2.3% higher specific investment cost than R245fa, while n-Pentane and Isopentane exhibit more than 15% cost rise. Thus, from the thermo-economic scale with an extended application range, R1233zd(E) exhibits a better overall performance index when compared with other R245fa alternatives and can be serviced as promising candidate to replace R245fa.

为了加快有机朗肯循环 (ORC) 系统的高全球变暖潜能值 (GWP) 工作流体更换过程，与其他天然流体相比，已对作为 R245fa 替代品的低 GWP 流体 R1233zd(E) 进行了热经济评估用于地热应用的正戊烷、异戊烷和异丁烷。热源水质量流量保持恒定，蒸发器侧和冷凝器侧均设置 5 K 夹点。所有工作流体的净热效率接近 2%。将热源从 120 °C 增加到 160 °C 可使效率提高 20% 以上。异丁烷的临界温度较低，限制了其在 160 °C 热源中的应用。R1233zd(E) 显示出与 R245fa 相近的质量流量（在 2% 以内），而其他产品则表现出 40% 以上的流量降低。本研究还对组件级性能进行了调查。所有替代方案都表现出比基准 R245fa 更低的蒸发器侧（蒸发器和预热器）传热面积，以及略高的冷凝器侧（冷凝器和减温器）传热面积。对于涡轮机性能，R245fa 显示出最高的体积流量比，表明膨胀过程的入口和出口点之间的转子叶片高度应发生显着变化。R1233zd(E) 的涡轮机尺寸参数比基线增加了约 10%，正戊烷增加了约 22%，异戊烷增加了约 11%，而异丁烷减少了 32%。一般而言，R1233zd(E) 的特定投资成本仅比 R245fa 高约 2.3%，而正戊烷和异戊烷的成本增加超过 15%。因此，