Life Cycle Impact Assessment Of Ground Source Heat Pump System In Cold Area

With the improvement of comfort requirements, energy consumption which is used to do improve the indoor environment is increasing in the air conditioning system year by year. What make the human to realize the importance of energy conservation and environmental protection are bad living environment and the shortage of energy resources. The geothermal energy has many advantages, such as, stable operation efficiency, saving energy and water, clean and environmental protection, so ground source heat pump has become the focus of research. However, popularization and application is limited by larger initial investment of ground source heat pump system. What has important significance to promote the development of ground source heat pump system is making certain environmental impact and amount of energy saving.This paper constructs life cycle impact assessment model of ground source heat pump system in the cold area. The ground source heat pump system is divided into four subsystems, including geothermal energy exchange system, building pipelines system, machine room equipment and auxiliary heating device system and end equipment system. This paper determines system boundary and research scope of four subsystems respectively, and checks out life cycle stage of the great environmental influence, and ignores life cycle stage of the less affected. Using EnergyPlus software, this paper builds typical building model of the ground source heat pump air conditioning experiment platform system of the cold areas. A yearly cold and hot load and energy consumption of experiment platform are simulated, and the power consumption of each device in operation and maintenance phase is gotten. The typical ground source heat pump system is carried on the analysis of energy consumption. The research results show that energy consumption of raw materials’ production and transportation stage and operation and maintenance stage accounts for the proportion of the total energy consumption is the largest, 13.4% and 86.3%, respectively, equipment installation and transportation stage and disposal phases accounts for the proportion of the entire life cycle is very small, about 0.3%.In addition, a typical ground source heat pump system is carried on the life cycle impact assessment. The results showed that what has an important impact on environment is operation and maintenance phase, accounted for more than 80%, the second is the raw material production and transportation period, accounting for about 15%. This paper analyzes each life cycle phase proportion in different environmental impact types.Finally, the paper puts forward operation scheme of the typical ground source heat pump system in the system design and operation management. Operation energy consumption of the control strategies that are improving air conditioning design temperature in the summer and fan coil intermittent operation are simulated by EnergyPlus software to calculate the energy saving rate of two strategies. Compared with the operation energy consumption of the typical ground source heat pump system, the energy saving rate of improving air conditioning design temperature in the summer is 14.1%, and the energy saving rate of fan coil intermittent operation is 5.7%.