Performance assessment of high temperature heat pump working with different configurations in combination with internal heat exchanger, economizer and subcooler

High temperature heat pump (HTHP) represents a pivotal method of decarbonizing for industrial heat application. The impact of different configurations on the thermodynamic performance of HTHP is significant. However, the impact of different configurations of internal heat exchanger (IHX), economizer and subcooler on the performance of HTHP is more discussed theoretically and has not been explored experimentally. This study evaluated HTHP performance in different modes at outlet temperatures ranging from 85 °C to 125 °C, employing the 85 °C basic mode as the evaluation criterion. Furthermore, the analysis of exergy losses and economic was conducted. The result showed that the system exhibited excellent heating performance, achieving an optimal balance between efficiency and cost with an increase of 11.97 % in heating capacity and 4.43 % in COP at only-vapor injection mode. Compared to economizer, IHX has limited effect on system performance. Subcooler increased the subcooling by more than 10 °C, but it did not significantly increase the heating capacity. In terms of exergy losses, the use of IHX reduced the total exergy destruction by 10.62 %. The use of economizer increased the total exergy destruction to 133.41 kW, an increase of 11.87 %. The total exergy destruction increased as the outlet temperature increased and reached 158.22 kW at 95 °C outlet temperature. 85 °C only-vapor injection mode has the shortest payback period of 1.44 years. The selection and adjustment of the heat transfer equipment in the HTHP should be informed by a comprehensive understanding of the specific working conditions and demands to ensure the optimal economic efficiency of the system.