Characteristics of Ground Source Heat Pump System (GSHP)
C. good long-term economy
The initial investment cost of ground source heat pump system is higher than that of conventional coal-fired boiler heating system and cogeneration central heating system. However, this comparison does not calculate the investment of traditional heating and transportation infrastructure, nor does it quantify the cost savings of the ground source heat pump system, which can refrigerate, provide fresh air and hot water in addition to heating. Therefore, although the initial investment of ground source heat pump system is large, the operation and maintenance cost is low, and the incremental payback period of investment is about 4 to 10 years.
Problems needing attention in ground source heat pump system
1. Balance of exothermic and absorbing heat from geological sources
For some areas, the heat and cold loads are not uniform in winter and summer, so the difference between discharging underground heat and absorbing underground heat will increase year by year, resulting in the decrease of heat pump efficiency year by year, and destroying the heat balance of ground sources. Therefore, the characteristics of cold and heat demand should be fully taken into account in different regions. Compensation measures should be taken to reduce heat imbalance in regions with large difference.
2. Effects on soil environment
For the buried pipe heat pump system, the drastic change of soil environmental temperature will lead to dramatic changes in soil microbial environment. The burial depth of soil heat exchange also determines the influence of the system on plant roots, soil microorganisms and building foundations.
3. Surface water source heat pump system is greatly affected by natural conditions.
Because surface water temperature is greatly affected by climate, similar to air source heat pump, the lower the ambient temperature, the smaller the heat supply of heat pump, and the COP of heat pump will also be reduced. The cooling and heat load that a certain surface water body can bear is related to its area, depth and temperature and other factors, which need to be calculated according to the specific situation.