The energy consumption of refrigeration systems has significantly contributed to indirect emissions, exacerbating global warming. The introduction of nanofluid technology, which involves suspensions of nanoparticles, has demonstrated remarkable enhancements in heat transfer efficiency for refrigeration applications, alongside a notable decrease in energy consumption. This study was conducted to mitigate indirect emissions from refrigeration systems. Specifically, the research evaluates the performance of aluminum oxide nanoparticle-based suspensions in vapor compression refrigeration (VCR) systems under varying refrigerant mass charges. The experimental investigation utilized isobutane R600a, which has a much lower global warming potential. Al2O3 nanofluids were prepared using mineral oil. The nanofluid is prepared in varying concentrations from 0.02 wt.% to 0.01 wt.%. Refrigerant charges of 150 g, 180 g, and 200 g of R600a were tested for each nanofluid composition. The experimental outcomes revealed significant performance improvements. For the combination of 200 g of R600a-MO with a 0.1 wt% Al2O3 suspension, the results included a 39.8% increase in Coefficient of Performance. Additionally, the use of nanosuspension led to a considerable decrease in exergy destruction across various components of the refrigeration system when compared to pure refrigerants.