Development of Integrated Air Conditioning Systems Utilizing Low-Global Warming Potential (GWP) Refrigerants in Compliance with the Kigali Amendment: A Mathematical Modeling and Optimization Approach
DOI:
https://doi.org/10.65204/djes.v3i1.393Keywords:
Low-GWP refrigerants, Multi-objective optimization, Total Equivalent Warming Impact (TEWI), System re-optimization, Kigali Amendment complianceAbstract
The Kigali Amendment is leading to a rapid global phase-down of high-GWP refrigerants, which will require the thoughtful redesign of vapor compression systems to achieve the same performance while mitigating environmental impact. In this work, we developed a hybrid mathematical and computational framework that includes thermodynamic modeling, surrogate-based forward simulation, and multi-objective Pareto optimization to study and compare refrigerants R-410A, R-32, R-1234ze(E), and R-717. We used synthetic yet physically-consistent datasets to predict both coefficient of performance (COP) and total equivalent warming impact (TEWI) under reasonable operating conditions and real-world scenarios. We found that while low-GWP fluids provide a path to low-impact thermal mechanical systems, there are fundamental trade-offs associated with efficiency and climate impact that need to be considered when transitioning from high-GWP fluids. Based on optimization, we recommend R-1234ze(E) and R-717 as the two best low-GWP fluids with the potential of continued use over the long-term to support regulatory compliance, while R-32 continues to be efficient switching fluid during transitions. The framework gives a scalable and reproducible guidance tool to assist in refrigerant selection in line with the urgency of meeting Kigali phase-down targets, and in the context of wider objectives for both sustainable energy and carbon mitigation.
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