Load Characteristics Analysis of Water-Source Heat Pump System for Harvesting Waste Heat from Small Data Centers

The power usage limit becomes lower with the green development of data centers. The small liquid cooling device is emerging as a new cooling option for small data centers with high energy density, which helps recover the waste heat. In this paper, the energy efficiency characteristics of three types of water-source heat pump systems under different surplus heat conditions are compared and analyzed in the surplus heat load range of small data centers. The energy efficiency of the water-source heat pump system is distributed at 5-7, 5-6, and 4.5-6.5 on the source side, transmission and distribution side, and user side, respectively. When the user-side heat load is retained at 0 kW to 1 750 kW and 2 500 kW to 3 200 kW, the energy efficiency of the source-side enhanced water-source heat pump system is highest. When the user-side heating load demand is 1 750 kW to 25 00 kW, the energy efficiency of the source-side enhanced water-source heat pump system is near that of the transmission and distribution-side enhanced water-source heat pump system. Finally, the coupling matching formula <italic>Q</italic>_N=<italic>kQ</italic>_S is obtained between the user-side heat load demand and data center surplus heat load, in which <italic>k</italic> ranges from 1.196 2 to 1.364 2.