Research Of Energy Saving Efficiency Of River Water Source Heat Pump In Office Building

In view of energy efficient of heat pump theoretically and environment friendly of water used as cold and heat source,water source heat pump has prominent advantage in the air conditioning system.The building form and rest will influence strongly the building load and the energy consumption of air-condition terminal equipment,which impacts energy saving efficient of water source heat pump.Chongqing,with abundant water,is selected as research site,and it is analyzed specifically that energy saving efficient and application feasibility of water source heat pump.Water source heat pump system has a large initial investment,so its conventional application in large public buildings.As an emerging economic developing city,Chongqing has a lot of office buildings.With brief analysis of geographical conditions and economic development scale in Chongqing,it is confirmed that energy saving efficient of water source heat pump applied in office buildings.In order to evaluate specifically energy saving efficient of river water source heat pump,energy consumption yearly is compared between water source heat pump and conventional cold and heat source system(water chilling unit+hot water boiler).To this end it is established that energy consumption yearly model of river water heat pump.Fan coil with independent fresh air unit,indoor air condition terminals,is a flexible application,which is used in office building and building load is obtained.The energy consumption of conventional cold and heat source system is calculated through software DeST.The energy consumption of river water heat pump includes energy consumption of heat pump units and energy consumption of water system.The performance curve(power-load rate curve),provided by equipment manufacturer,results in the fitting formula of heat pump energy consumption.Combining fitting formula and hourly building load obtains the yearly energy consumption of heat pump.The relationship between lift and flow rate of water pump is approximately parabola,which could be indicated as second power polynomial.Meanwhile,the shaft power of water pump could be expressed as ratio of the product of lift and flow rate and efficiency.Consequently,the shaft power of water pump could be indicated approximately as third power polynomial.With the fitting formula of shaft power and flow rate,the shaft power of water pump could be calculated according to the“a pump for a machine”principle.After calculation,river water source heat pump system consumes electricity 269 575 kW·h in cooling period,consumes electricity 80 9955 kW·h in heating period.The conventional cold and heat source system consumes electricity 329 962 kW·h in cooling period,consumes electricity 8 182 kW·h,natural gas 20 865 Nm~3.Taking the price level and civil construction quota into consideration,it is confirmed that the yearly operation cost and initial investment of the two systems.According to the calculating result,the yearly operation cost of water source heat pump system and conventional cold and heat source system are 230 300 yuan and 334 300 yuan respectively.The initial investments of water source heat pump system and conventional cold and heat source system are 4 370 000 yuan and 4 258 000 yuan respectively.Through life-cycle assessment method,the dynamic recovery period of river water heat pump system is 2.96 years compared to conventional cold and heat source system.Water source heat pump system shows outstanding economic benefits.It is confirmed that load rate is the main influence of water source heat pump performance.The fitting formulas of cooling and heating condition are presented with“third power ten coefficient”principle.With the use of software PHOENICS and heat-conduct theory,it is analyzed that the influence of water source heat pump on the water intake in Jialing River in Chongqing,which indicates that the application of water source heat pump is weakly influent on river.The feasibility of water source heat pump is proved.