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This paper explains a thorough exergy analysis of the most important reactions in soil–plant interactions. Soil, which is a prime mover of gases, metals, structural crystals, and electrolytes, constantly resembles an electric field of charge and discharge. The second law of thermodynamics reflects the deterioration of resources through the destruction of exergy. In this study, we developed a new method to assess the exergy of soil and plant formation processes. Depending on the types of soil, one may assess the efficiency and degradation of resources by incorporating or using biomass storage. According to the results of this study, during different processes from the mineralization process to nutrient uptake by the plant, about 62.5% of the input exergy will be destroyed because of the soil solution reactions. Most of the exergy destruction occurs in the biota–atmosphere subsystem, especially in the photosynthesis reaction, due to its low efficiency (about 15%). Humus and protonation reactions, with 14% and 13% exergy destruction, respectively, are the most exergy destroying reactions. Respiratory, weathering, and reverse weathering reactions account for the lowest percentage of exergy destruction and less than one percent of total exergy destruction in the soil system. The total exergy yield of the soil system is estimated at about 37.45%.

Pneumatic systems are widely used in industrial manufacturing sectors. However, the energy efficiency of pneumatic systems is generally much lower than their hydraulic and electric counterparts. It is necessary to explore more elaborate theories and methods for achieving better energy performance in pneumatic systems. In this study, for investigating the interaction effects between pneumatic components and the accessible improvement potential of energy efficiency in a pre-existing pneumatic system, the advanced exergy analysis is conducted with a better understanding of exergy destruction. The conventional exergy analysis is also carried out for comparison. The results show that an exergy efficiency of 17.3% could be achieved under the real condition in the case of the investigated pneumatic system. However, under unavoidable conditions, the theoretical maximum exergy efficiency could reach 70.5%. This means there is a significant potential for improving the energy performance of the investigated system. Furthermore, both conventional and advanced exergy analyses indicate that the pneumatic cylinder has the greatest potential for improvement. The advanced exergy analysis reveals the complex and variable interactions between pneumatic components. It highlights that the exergy destruction of some components is caused by other components in the system, and thus, improving energy efficiency at the system level rather than at the component level is of great significance. Besides, a priority order of all pneumatic components is determined, thereby guiding the improvement of the energy efficiency of the pneumatic system.

Rapid development in the renewable energy sector require energy storage facilities. Currently, pumped storage power plants provide the most large-scale storage in the world. Another option for large-scale system storage is compressed air energy storage (CAES). This paper discusses a particular case of CAES—an adiabatic underwater energy storage system based on compressed air—and its evaluation using advanced exergy analysis. The energy storage system is charged during the valleys of load and discharged at peaks. The model was built using Aspen HYSYS software. Advanced exergy analysis revealed interactions between system components and the potential for improving both system components individually and the system as a whole. The most significant reduction in exergy destruction can be achieved with heat exchangers. The round-trip efficiency of this system is 64.1% and 87.9% for real and unavoidable operation conditions, respectively.

Electricity access and reliability in Nigeria is poor due to obsolete power distribution infrastructure. This could be improved by deploying wind energy resources. The present research assessed the thermo-economic, advanced and extended exergy analysis of deploying wind turbine for distributed generation in four Nigerian locations. The air temperature and wind speed of the sites was used together with Weibull statistical parameters to mathematically model the thermodynamic performance of selected wind turbine for the sites. The results show that the energy and standard exergy efficiency of the sites ranges from 0.16 – 0.44, 0.05 – 0.37, 0.23 –0.39, 0.26 – 0.37 and 0.12 –0.33, 0.04 – 0.25, 0.17 – 0.28, 0.18 – 0.28 respectively for Enugu, Kaduna, Katsina and Jos. The exergy efficiency based on the extended exergy analysis (EEA) approach was found to be much lower than the standard exergy efficiency for all the sites. Based on EEA, Enugu, Kaduna, Katsina and Jos has exergy efficiency of 1.05, 0.73, 2.52 and 3.22 % respectively. Economic performance results showed that Jos is the best site with least monthly average COE value of 0.15$/kWh which compares closely with global average COE value of 0.14 $ /kWh for households. Katsina and Enugu have a COE value of 0.19 and 0.84$/kWh respectively while Kaduna is the worst in performance with highest COE value of 1.13 $ /kWh. 

Exergy analysis and advanced exergy analysis of an absorption chiller/Kalina cycle integrated system are conducted in this research. The exergy destruction of each component and overall exergy efficiency of the cascade process have been obtained. Advanced exergy analysis investigates the interactions among different components and the actual improvement potential. Results show that among all the equipment, the largest exergy destruction is in the generators and absorber. System exergy efficiency is obtained as 35.52%. Advanced analysis results show that the endogenous exergy destruction is dominant in each component. Interconnections among different components are not significant but very complicated. It is suggested that the improvement priority should be given to the turbine. Performance improvement of this low-grade waste heat recovery process is still necessary because around 1/4 of the total exergy destruction can be avoided. Exergy and advanced exergy analysis in this work locates the position of exergy destruction, quantifies the process irreversibility, presents the component interactions and finds out the system improvement potential. This research provides detailed and useful information about this absorption chiller/Kalina cycle integrated system.

This study evaluates the performance of an evacuated tube indirect solar dryer (ETISD) for drying tilapia strips at three thicknesses (4, 8, and 12 mm) using computational fluid dynamics (CFD), energy-exergy analysis, and sustainability indicators. CFD simulations were employed to analyze airflow patterns, temperature distribution, and velocity profiles inside the drying room (DR) across five air velocities (0.02–0.06 m/s). The optimal air flow rate of 0.03 m 3 /s provided a uniform drying temperature of 74.82 °C, at solar noon. Simulations over two consecutive drying days (8 a.m.–5 p.m.) further assessed thermal and aerodynamic behavior, enhancing system optimization. Energy analysis revealed that the evacuated tube solar collector (ETSC) achieved a maximum input energy of 1311.8 W and useful energy of 682.5 W, with energy efficiencies of 44.5–51.2% (ETSC) and 16.18–21.57% (ETISD). Exergy efficiencies ranged from 8.51 to 21.99% (ETSC) and 29.23–84.76% (ETISD), highlighting thermodynamic performance. Sustainability indicators, including improvement potential (IP) (2.71–6.69 W), waste exergy ratio (WER) (1.15–1.36), and sustainability index (SI) (1.09–1.28), demonstrated the system’s environmental and operational viability. These findings underscore the ETISD’s effectiveness for sustainable tilapia drying, balancing energy efficiency, thermal performance, and ecological impact.

Solar energy is secure, clean, and available on earth throughout the year. The PV/T system is a device designed to receive solar energy and convert it into electric/thermal energy. Nanofluid is a new generation of heat transfer fluid with promising higher thermal conductivity and improve heat transfer rate compared with conventional fluids. In this review, the recent studies of PV/T using nanofluid is discussed regarding basic concept and theory PV/T, thermal conductivity of nanofluid and experimentally and theoretically study the perfromance of PV/T using nanofluid. A review of the literature shows that many studies have evaluated the potential of nanofluid as heat transfer fluid and optical filter in the PV/T system. The preparations of nanofluid play an essential key for high stability and homogenous nanofluid for a long period. The thermal conductivity of nanofluid is depending on the size of nanoparticles, concentration and preparation of nanofluids.

The paper contains a simplified energy and exergy analysis of pumps and pipelines system integrated with Thermal Energy Storage (TES). The analysis was performed for a combined heat and power plant (CHP) supplying heat to the District Heating System (DHS). The energy and exergy efficiency for the Block Part of the Siekierki CHP Plant in Warsaw was estimated. CHP Plant Siekierki is the largest CHP plant in Poland and the second largest in Europe. The energy and exergy analysis was executed for the three different values of ambient temperature. It is according to operation of the plant in different seasons: winter season (the lowest ambient temperature Tex = −20 °C, i.e., design point conditions), the intermediate season (average ambient temperature Tex = 1 °C), and summer (average ambient temperature Tex = 15 °C). The presented results of the analysis make it possible to identify the places of the greatest exergy destruction in the pumps and pipelines system with TES, and thus give the opportunity to take necessary improvement actions. Detailed results of the energy-exergy analysis show that both the energy consumption and the rate of exergy destruction in relation to the operation of the pumps and pipelines system of the CHP plant with TES for the tank charging and discharging processes are low.

In this paper is performed energy and exergy analysis of waste heat recovery closed-cycle gas turbine system. Analyzed system can use waste heat from various main propulsors (gas turbines or internal combustion engines). Basically, the observed system operates by using CO2, what was the baseline for the analysis. It is investigated did the observed system, while retaining the same configuration, can operate with different operating mediums instead of CO2. Other observed operating mediums were Air and Helium. During the change in operating medium, pressures and temperatures in some system operating points cannot remain the same as in the process with CO2, but the intention was to perform only the necessary changes (to ensure proper operation of each system component). Obtained results show that the system, while retaining the same configuration, can operate by using different operating mediums. Energy analysis of the system shows that the whole configuration is composed to operate with CO2, because the whole system energy efficiency is much higher than in operation with Air or Helium. The energy efficiency of the whole system during operation with CO2 is 87.68%, with Air is 58.39% and operation with Helium gives energy efficiency of 49.25%. Exergy analysis of the observed system shows that the system has a good potential to operate with other mediums, because in any observed situation exergy efficiency of the whole system was higher than 50%. In this analysis the highest exergy efficiency of the whole system was obtained during operation with Air (57.76%). In the observed system, low-temperature regenerator and main turbo-compressor are detected as components which are highly influenced by the change of operating medium. Therefore, these two components should be a baseline for further improvements and system optimization.

This research presents a novel Extended Thermodynamic Analysis Method (ETAM) to respond to the issue of 'which equipment holds the highest priority of receiving improvements in a thermodynamic cycle'. This novel analysis comprises three parts: extended energy, extended entropy, and extended exergy analyses. As a case study, a low-temperature geothermal Kalina cycle system-34 was analyzed. The results of Conventional Exergy Analysis Method (CEAM), Advanced Exergy Analysis Method (AEAM), and the proposed novel method were compared with each other. CEAM results indicate that the condenser, followed by the evaporator and turbine, has the most exergy destruction. In contrast, according to AEAM results, the top priority for improvement should be given to the condenser, followed by turbine and Low-Temperature Recuperator (LTR). The improvement priority using the presented novel extended analysis was also given to the condenser, turbine, and LTR, the finding being the same as the results of AEAM, while the proposed novel method is less complicated than the AEAM.