Comparative assessment and performance evaluation on different terminals driven by ASHP: Theoretical modelling and experimental comparison of different heating terminals

As a kind of sustainable energy technology, air-source heat pump (ASHP) is used for residential heating in most parts of northern China because of the characteristic of high efficiency and environmental protection. However, the heating terminal has a great influence on system efficiency and thermal comfort. To comparison evaluate the air-source heat pump combined with traditional steel radiator, new bimetal radiator and small temperature difference fan-coil unit (STDFCU), the theoretical simulation and experimental study of different heating terminals is conducted in this paper. The experimental setup has built to test the system efficiency and thermal comfort of ASHP combined with different heating terminals. The theoretical results show heating capacity with all kinds of heating terminals increases with hot water temperature rising. Under the same conditions, new bimetal radiator has over 11% heating capacity higher than traditional steel radiator because of its external air flow structure and the STDFCU provides the most heating capacity. By comparing the theoretical results and experimental data, the maximum calculation error is less than 10% which means the calculation results are compared with experimental data in good agreement. The STDFCU has the best heating performance and shows the great potential on reducing hot water temperature and system power consumption for user. Selecting appropriate terminal and ASHP system can effectively improve the energy efficiency, reduce the power consumption and realize the energy saving. The research findings can be extended to the most regions and country in the world.