Modeling of a direct absorption parabolic trough collector based on using nanofluid: 4E assessment and water-energy nexus analysis

Abstract

Water and energy shortages are among the significant concerns of human life within the current century; thus, it is essential to save consumption of these resources everywhere, including in solar collectors. This study aims to numerically model the direct absorption parabolic trough collector (DAPTC) for low-temperature applications. In this paper, a comprehensive analysis of the energy, exergy, economic and environmental (4E) impacts of the collector at different geometric dimensions and operating conditions is conducted. The collector's embodied energy (EE), and the embodied water (EW) are investigated. The main finding of this study is that CuO + MWCNT/water hybrid nanofluid, MWCNT/water and CuO/water nanofluids can save about 40.44 GJ, 39.01 GJ, 30.8 GJ embodied energy as well as 59.03 KL, 56.95 KL, and 44.96 KL embodied water, respectively. Obtained results claim that a rise in the inlet temperature increases the exergy efficiency and relatively decreases the energy efficiency. Furthermore, lowering the inlet temperature results in a reduction of the cost of energy production. According to the numerical results, the highest accessible exergy and energy efficiencies are 36.63% and 65.47%, respectively, while the lowest energy production cost is 0.0195 $/kWh.