Climate-adaptive performance and environmental benchmarking of R600a refrigeration systems under tropical operating conditions

In the context of rising global temperatures and the urgent need for low-Global Warming Potential (GWP) alternatives, enhancing the climate adaptability of domestic refrigeration systems is essential for sustainable cooling. Tropical regions like India regularly experience ambient temperatures exceeding 35 °C, yet conventional energy rating protocols evaluate refrigerators under fixed and moderate conditions, which poorly reflect real-world usage. This discrepancy highlights a critical gap: the lack of performance data under dynamic, high-stress thermal environments that influence system efficiency, refrigerant behavior, and energy consumption. Addressing this, the present study experimentally investigates the thermodynamic behavior of a modified 190 L refrigerator using R600a, a natural hydrocarbon refrigerant with low global warming potential, under varying cabinet temperatures (0–15 °C) and ambient conditions (30–40 °C) that simulate tropical environments. Performance metrics such as evaporator heat absorption (Qₑᵥₐₚ), condenser heat rejection (Q cond ), power consumption, compressor discharge temperature, and coefficient of performance (COP) were measured and analyzed. Results showed up to 17% and 20% increases in Qₑᵥₐₚ and Q cond , respectively, with rising cabinet temperatures. A 10 °C ambient temperature rise caused an 11.2% COP drop and a ∼16% increase in discharge temperature, indicating considerable thermal stress. Findings were validated against IMST-ART simulations with deviations within ±5–7%. By shifting away from idealized, static test conditions, this study offers climate-responsive insights into the real-world performance of R600a systems. Academically, it introduces climate responsive coefficient of performance and sustainaibility index as advanced performance indicators that address both engineering and sustainability goals. Socio-economically, the study underscores the potential for carbon savings, energy-efficient appliance policy reform, and better refrigerant selection for developing nations. Academically, it introduces performance mapping techniques that integrate thermal efficiency with environmental and economic metrics. Socio-economically, the study underscores the potential for carbon savings, energy-efficient appliance policy reform, and better refrigerant selection for developing nations. This work calls for an urgent transition toward climate-adaptive testing standards and supports the development of cooling systems engineered for high-heat environments bridging the gap between lab performance and field realities in the global pursuit of sustainable refrigeration.