Improving the efficiency of solar-driven trigeneration systems using nanofluid coolants

Abstract

This article is intended to evaluate methods to improve the efficiency of trigeneration plants, which are designed for the co-generation of heat, electricity, and cold. The possibility of using nanofluids with the addition of oxides of aluminum, silicon, magnesium, and copper, as well as copper itself in the concentration range of 1–6% has been analyzed. The results show that the use of nanofluids can increase the exergic efficiency of the system to 22.9–27.8% and increase thermal efficiency by 23.2–26.7%. It was found that nanofluids have low heat capacity, which may be one of the factors that increase the overall efficiency of trigeneration plants up to 43–60%. Magnesium oxide proved to be the most efficient for generating electricity, with 212.8 kW, aluminum oxide (197.5 kW) for cooling, and copper oxide for generating 98 kW of heat. The Pearson criterion was χ2 = 0.87, Student’s t-test 0.07–0.09, statistical significance of results p ≤ 0.005.