Research Of The Ground Source Heat Pump Composite Cooling Tower System And Life Cycle Assessment

As a new type of HVAC technology that utilizes renewable resources,ground-source heat pump(GSHP)is an internationally-used high-efficiency energy-saving technology in the field of building energy conservation.However,under normal circumstances,the building can't meet the same cooling and heating load.This kind of imbalance between heat extraction and heat emission may result in the collapse of the geothermal field.Therefore,the single ground source heat pump system cannot be widely used.The research of heat pump composite system is very important for the development of GSHP.At the same time,in the design process of ground source heat pump,soil temperature is very important for the design of buried pipe.It is not possible to directly obtain local soil temperature due to objective conditions.An accurate and practical method for predicting soil temperature for ground source heat pump system design and heat calculation.Programming is crucial.On the other hand,95% of the existing buildings do not meet the building energy-saving standards.With the development of energy-saving and emission reduction,the problem of energy-saving renovation of existing buildings is becoming more and more prominent.As a powerful measure for energy-saving renovation of buildings,GSHP's adaptability is an important factor for its development.The comprehensive evaluation of composite systems in a more scientific way is of great significance for the development of GSHP composite systems.This project is based on the transformation project of a hospital in Pistoia,Italy,to establish a composite system model.In order to improve the accuracy of modeling,a prediction model is adopted for the important parameter of soil temperature.We optimized the model and verified the accuracy.,and the scope of use and prediction efficiency of the model are improved.In the accuracy verification of the model,the root mean square error of the optimized model is 1.6°C~3.2°C compared with the measured temperature lower than the classic model which is 1.8°C~3.9°C.Through the established composite system model,the long-term operation of the composite system was studied.The COP and soil temperature of the heat pump unit did not change significantly during the 20-year operation.In addition,based on the theory of full life cycle assessment(LCA),this project builds the LCA system of the composite system,and carried out LCA calculation.According to the LCA method we evaluated the system in terms of energy consumption,resource consumption and environmental impact.The largest proportion of energy consumption is the operation and maintenance phase of the system,with a specific gravity of 98.89%;the system's resource consumption coefficient is 187.51 E-03 equivalent;the environmental impact load is 2.03 standard equivalent.This project combines the actual project to build a ground source heat pump composite system,optimize the soil temperature prediction model,build a composite system LCA system,and proposes energy saving and emission reduction recommendations based on LCA results,which can provide reference for green building standards.It has certain significance for the application design and promotion of ground source heat pump.