Techno-economic analysis on frosting/defrosting operations for an air source heat pump unit with an optimized multi-circuit outdoor coil

Air source heat pump (ASHP) units are used in applications around the world. After optimizing the multi-circuit outdoor coil by installing water collecting trays between circuits and adjusting the refrigerant distribution by using valves located at each circuit, system frosting/defrosting operation performances could be effectively improved. Before practical industry-scale application of trays and valves, their economic performances should be evaluated. However, in current literature, techno-economic analysis on operation performance of ASHP units is rare, which limits the development of innovative technologies. Therefore, a techno-economic analysis on frosting/defrosting operations is carried out in this study. Firstly, the frosting/defrosting experiments are introduced, followed by a series of assumptions and calculations. Then, the economic analysis results are provided in detail. Compared with a traditional ASHP unit, the total running costs of the modified unit in the heating season could save as much as 3681.75 CNY, or 10.33%, and the total cost decreased by 3516.75 CNY, or 4.67%, over 15 years of service life. The payback period of the additional initial cost is less than 8 months. Contribution of this work plays an important role in the evaluation and application of new technologies in the HVAC field.