A hybrid H2O/IL absorption and CO2 compression air-source heat pump for ultra-low ambient temperatures

作者：Wu, Wei^*; Zhai, Chong; Huang, Si-Min^*; Sui, Yunren; Sui, Zengguang; Ding, Zhixiong

来源：Energy, 2022, 239: 122180.

DOI：10.1016/j.energy.2021.122180

• Hybrid heat pump
• Cold climate
• Absorption heat pump
• Ionic liquid
• Space heating

Heat pumps are promising for carbon neutrality. However, the existing vapor-compression heat pumps suffer from severe performance deterioration while the absorption heat pumps rely on toxic NH3-based fluids in sub-zero conditions. Therefore, a novel hybrid H2O/ionic liquid absorption and CO2 compression air-source heat pump is proposed for ultra-low ambient temperatures. The verified property and cycle models are used for performance optimization, characterization, and comparison. The coupling temperature that oppositely affects the efficiencies of the two sub-cycles is optimized to be 6 degrees C. With the ambient temperature rising from -30 degrees C to 0 degrees C, the primary energy efficiency (PEE) increases from 1.064 to 1.256, higher by 18-40% compared to a gas boiler. The heating capacity stably ranges in 94.0-102.9 kW, significantly increasing the reliability in cold climate. As the driving temperature rises from 96 degrees C to 130 degrees C, the PEE slightly varies in 1.155-1.190, while the exergetic coefficient of performance decreases from 0.609 to 0.600, encouraging the use of low-temperature heat sources (e.g., 100 degrees C). Compared to existing heat pumps, the hybrid heat pump efficiently operates at -30 degrees C, showing the highest PEE for most sub-zero conditions with much slower heating capacity deterioration. The advantage is much higher under colder conditions.

• 单位
  东莞理工学院