Improving the efficiency of a CO₂ heat pump for simultaneous heating and cooling coupled with an ambient source.

The CO2 heat pump for simultaneous heating and cooling (CO2 HPS) is an efficient technology capable of providing both heating and cooling within a single system. With its high energy efficiency and low carbon emissions, the CO2 HPS has attracted growing attention in both industry and academia. However, the basic CO2 HPS does not effectively balance the heating and cooling output with the actual load demands, leading to unnecessary energy waste and lower overall system efficiency. To address this issue, this paper proposes four new configurations that introduce ambient sources to regulate the heating and cooling supply-demand balance, while also improving the system structure through the integration of heat recovery and ejector-based loops. These enhancements enable the unit to flexibly and efficiently adjust heating and cooling output according to actual load requirements. The results show that, compared to the basic configuration, the overall coefficient of performance of the four new configurations increases by 0~14.69 %, 2.77~19.81 %, 5.66~17.70 %, and 0.61~8.40 %, respectively.