Effect of multi-source uncertainty on performance of surface water-source heat pump systems

There are a lot of uncertainties that cannot be ignored in the simulation of water-source heat pump systems, and they can be divided into the model uncertainty and the parameter uncertainty according to the source. This paper quantitatively analyses the effects of model uncertainty and parameter uncertainty on the performance of surface water-source heat pump systems. Thirteen empirical models of heat pump units are selected and verified. The uncertain parameters considered include the uncertain parameters on the load side and on the system side, and the results discussed include system energy consumption, energy saving and economy. The global sensitivity analysis method is used to analyse the influence of various uncertain factors on the system performance. The results show that the multi-source uncertainty has a significant impact on the performance evaluation of the water-source heat pump system, the cumulative energy consumption of the system is 264 t to 1 107 t throughout the year, and the energy saving rate is -78.5% to 32.0% compared with the traditional air conditioning system.The net present value of the system investment is -4.16 to 6.63 million yuan after 20 years of operation, and the probability that the energy saving rate and the net present value of investment are negative is 23% and 8%, respectively. The most significant factors affecting the uncertainty quantization results are outdoor meteorological parameters, COP of heat pump unit, heat pump model, personnel and outdoor air volume.