Simulation driven design approach and prototype development for low-cost high-efficiency room air conditioners using next generation refrigerants

The global refrigerant transition requires the redesign of heating, ventilation and air-conditioning (HVAC) systems. Higher efficiency systems also reduce peak loads and allow better integration of secure, affordable, reliable base-load generation technologies. However, many small and medium-sized air conditioner (AC) manufacturers, particularly in developing and emerging economies, lack the technical capacity to design affordable, energy-efficient systems using next generation refrigerants. This study presents a simulation-driven design approach for developing cost-effective, high-efficiency mini-split AC prototypes using R32, R454B, and R290. Physics-based system models were developed in VapCyc® and CoilDesigner® to conduct component-level simulations and system optimization. Cost analysis was performed to minimize material costs, and optimal designs were validated under ISO 5151 conditions in a psychrometric chamber. All prototypes achieved 33% higher EER and nearly doubled cooling seasonal efficiency compared to reference units, with only a 2–16% increase in material cost. These results indicate an approximately twofold reduction in peak load and emissions at comparable cost. The proposed simulation-driven methodology shortens the product development cycle and enables reliable, high-performance, next generation AC designs, offering a practical pathway for manufacturers in emerging markets to accelerate the transition to sustainable cooling technologies, meeting grid reliability constraints, environmental regulations and market demands for affordability.