Comparison of two novel geothermal-powered cooling systems based on 4E evaluations

In this research, two innovative cooling systems are introduced that utilize low-temperature geothermal energy as an alternative to fossil fuels. Systems A and B utilize different subsystems: A uses the organic Rankine cycle (ORC), Kalina cycle (KC), and vapor compression refrigeration cycle (VCRC), while B integrates KC, VCRC, and the absorption refrigeration cycle (ARC). The proposed systems were analyzed using multiple techniques, including energy analysis, conventional exergy analysis (CEA), exergo-economic analysis (EEA), and advanced exergy analysis (AEA). Based on the results obtained, system A shows a modified exergy efficiency of 25.6% and a total cost of 117.9 $/s, while system B demonstrates an efficiency of 36.7% and a total cost of 35.3 $/s. Therefore, the proposed systems perform better thermodynamically and economically when using ARC rather than ORC. CEA states that specific components such as evaporators and generators, undergo significant exergy destruction. On the other hand, the AEA indicates that for both systems A and B, the most significant avoidable endogenous exergy destruction is related to VCRC's condenser (37% for system A, 30.2% for system B), followed by the compressor (21% for system A, 17.2% for system B) and KC's condenser (10.1% for system A, 13.2% for system B). Therefore, CEA and AEA prioritize components improvement differently. Based on the exergy destruction cost rate, the EEA recommends prioritizing the improvement of the VCRC's condenser (29.2% for system A, 23.8% for system B), VCRC's valve (17.39% for system A, 14.19% for system B), and compressor (14.2% for system A, 9.9% for system B). Accordingly, the EEA and AEA have different priorities for improving components, which should be considered based on the goal, whether it's cost-saving or system efficiency. It has also been discovered that a considerable amount of avoidable exergy destruction in system A is exogenous in the ORC (84.4%) and KC (83.4%), while endogenous in the VCRC (61.83%). Consequently, optimizing the VCRC can significantly improve system A's performance. Similarly, the VCRC should be prioritized to enhance system B's performance. The findings of this study can be used to inform decision-making and optimize the design and operation of the proposed systemsQuery.