Abstract
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Various methods are devised to capture renewable energy or waste heat from different sectors, where among all, waste heat capturing from the generator of a wind turbine through the cooling process for freshwater and cooling production is paid less attention in Iran, in spite of the fact that many wind farms in Iran are in hot and humid regions and the residents nearby the farms desperately need freshwater and cooling load. To surmount this problem, waste heat extraction from a wind turbine (Enercon 70 Model) for freshwater and cooling production is proposed in this study. Instead of dissipating this thermal energy of the wind turbine into the environment, it can be used for freshwater and cooling production. Meantime, the use of nanoparticles increases the heat transfer rate of the cooling process in the wind turbines, and hence more freshwater and cooling can be obtained. This concept is also accounted for in this study by presenting thermodynamic and thermoeconomic modeling of a new trigeneration system, using three types of nanoparticle namely Cu, CuO, and TiO2 in the base fluid of water. The results showed that Cu/water nanofluid had the highest performance since it produced more freshwater and cooling capacity, while TiO2/water mixture had the lowest performance. In comparison with the reference system, 7.135 kW power can be saved for a cooling capacity of 56.6 kW if the proposed system is used at a wind speed of 12 m/s. Increasing Cu concentration from 0.5% to 7% increases the freshwater rate from 126.9 L/day to 144.5 L/day, cooling load from 5.1 kW to 5.8 kW, supply air volume rate from 9.27 to 10.56 , energy efficiency from 45.47% to 51.68%, and exergy efficiency from 11.04% to 12.12%. At last, two cities of Manjil and Kahak are selected as case study benchmarks and the results are further expanded for each case.
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