This study presents a platform that focuses on the improvement of the performance of trans-critical CO₂ refrigeration systems to face the big demand of economic and friendly cooling technologies, reduce environmental impact, and reduce operational costs. Four different refrigeration cycles were studied: abase cycle with 14 kW nominal capacity, a two-stage compression cycle, a cycle with R448a mechanical subcooling and a hybrid cycle that incorporates the two modifications. The Engineering Equation Solver (EES) software is used to analyze the different cycles under different operating parameters that includes gas cooling outlet temperature (35–50°C), evaporation temperatures (0–10 °C), compressor efficiencies (0.6–0.9), and gas cooler pressures (8,000–12,000 kPa). All modified cycles show more enhanced performance than base cycle. The hybrid cycle reached the highest coefficient of performance with an average enhancement of 55.3%, followed by mechanical sub-cooling cycle with (46.1%) average enhancement and two-stage compression cycle with (7%) average enhancement. The analysis showed that the hybrid cycle reduced power consumption by about 7.1% compared to mechanical sub-cooling cycle and by about 6% compared to the base cycle. Also, the mechanical sub-cooling showed an increase of power consumption of 13.2% over the base cycle. The increase in ambient temperature from 35 °C to 50 °C resulted in about 35.5% increase in power consumption and a 40.1% decrease in coefficient of performance (COP). This study is novel because it evaluates the combination of two-stage compression refrigeration system cycle and a mechanical sub-cooling cycle under the effect of Jordanian climate conditions, conditions, which resulted in achieving higher performance, lower environmental impact, shorter payback period, and higher return on investment (ROI).
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