Thermodynamic and air emission analyses of low-GWP nanorefrigerants in a maritime vapour compression refrigeration system for R407C replacement (case study)

Addressing the decarbonisation imperatives of the maritime sector, this study conducts a theoretical energy, exergy, and emission analysis of a maritime vapour compression refrigeration system (VCRS). The objective is to evaluate low-Global Warming Potential (GWP) alternatives (R1234yf, R513A, R290, R1270) as replacements for the R407C utilised on the Badji Mokhtar III ferry. In this pursuit, this study investigates the specific integration of CuO and Al2O3 nanoparticles into these alternative fluids, providing a detailed assessment of their performance within the operational constraints of a large-scale maritime provisioning plant. A numerical model was developed in Python, leveraging the CoolProp library, and a density-based methodology was implemented to estimate the thermophysical properties of the nanorefrigerants. The results demonstrate that nanoparticle addition systematically enhances performance, with CuO notably offering superior gains over Al2O3. Hydrocarbons, specifically R290, emerge as the most promising solution. Quantitatively, the optimal configuration (R290 with a 0.04% mass fraction of CuO) achieves a 59% increase in the Coefficient of Performance (COP) and a 37% reduction in CO2 emissions (from 4.67 to 2.94 tonnes/month) compared to pure R407C. This work, therefore, concludes that the R290/CuO nanorefrigerant represents a highly effective solution for contributing to the environmental objectives of the maritime sector.HighlightsThermodynamic assessment of Al2O3 and CuO nanorefrigerants for maritime applications.Performance evaluation based on real-world data from the Badji Mokhtar III passenger vessel.Integration of hydrocarbons as sustainable, low-GWP alternatives to R407C in marine VCRS.Comparison of nanoparticle mass fractions (0.01%–0.05%) to optimise the environmental and energetic balance.