Thermodynamic, environmental, and exergoeconomic analysis of multi-ejector expansion transcritical CO2 supermarket refrigeration cycles in different climate regions of Türkiye

Abstract

Restrictions on high-GWP refrigerants have made the use of transcritical CO₂ refrigeration systems widespread. Using transcritical booster refrigeration cycle in warm climates is unsatisfactory due to its high energy consumption. This paper presents theoretical analysis and performance comparison of three different transcritical CO₂ supermarket refrigeration cycle configurations with ejector expansion in Türkiye, which has different climatic regions. Bin-hour data were derived using hourly dry-bulb temperature values for provinces from 7 different regions in Türkiye. The applicability of multi-ejectors to each modeled cycle was also investigated. Annual energy consumption and environmental impact reductions of up to 17% were obtained using ejector expansion cycle compared to booster cycle. Ejector expansion cycles achieved higher performance than booster cycle up to 46% in terms of exergy efficiency at investigated ambient temperatures. Unit product exergy costs of the ejector cycles were found up to 28% lower than booster cycle.