Experimental Evaluation of a Photovoltaic/Thermal Air Heater with Metal Mesh-Integrated Thermal Energy Storage System

The objective of this study is to improve the performance of a hybrid photovoltaic/thermal (PV/T) air heater incorporating a thermal energy storage system (TESS) that uses paraffin and has metallic mesh layers. In the experimental part of the research, three different pilot-scale PV/Ts have been designed, manufactured, and experimentally investigated. The first system was structured as a conventional PV/T, while the second (PVT/TESS) was modified with a paraffin-based TESS. The efficiency of a hybrid PV/T air heater was improved by integrating a paraffin-based thermal energy storage system (TESS) with metallic mesh layers (PV/T-MTESS). The performance of the modified PV/T-MTESS system was compared to two other PV/T systems under the same weather conditions and air flow rate. The results of the experiment demonstrated that the integration of mesh layers into the TESS led to substantial improvements in the system’s thermal and electrical performance, as well as its overall exergy efficiency. The improvements were 33.17%, 14.82%, and 58.15%, respectively, when compared to the unaltered (conventional) PV/T setup. Moreover, an enviro-economic analysis has been performed on the developed and tested PV/Ts. Using TESS with only paraffin and with mesh layer-added paraffin reduced the payback time of the system by 2.54% and 9.85%, respectively. Moreover, the annual carbon dioxide saving was improved from 0.079 tons/year to 0.103 tons/year using a mesh layer-integrated TESS in the PV/T air heater

Advanced Exergoeconomic Assessment of CO₂ Emissions, Geo-Fluid and Electricity in Dual Loop Geothermal Power Plant

Binary geothermal power plants (GPPs) are mostly encountered in geothermal fields with medium and low temperatures. The design and operation of dual binary GPPs can be difficult due to the geothermal fluid properties. This affects their performance and feasibility. Thermoeconomics are essential elements for the design and operation of the GPPs. In this study, advanced exergoeconomic analysis is applied to a true dual binary GPP (as a case study) to further evaluate it from performance and economic perspectives. In analysis, the specific exergy cost (SPECO) method is used. Then, some specific indicators are presented to evaluate the performance and economics of the GPP. Thus, technical and economic solutions have been developed in the design and operation stages through the analysis. The results of the study indicated that the total operating cost of 1218 USD/h could be reduced to 186 USD/h by improving the operating conditions. This corresponds to an 85% decrease. The cost per electricity generated, cost per geothermal energy input, and cost per CO2 emission of the GPP are determined as 0.049 USD/kWh, 5.3 USD/GJ, and 0.13 USD/kg, respectively. As a result, while the savings potential of the GPP is 15%, it can result in a 15% reduction in CO2 emission cost