Research On Post Evaluation System Of Green Building GSHP Application Effect Based On Measured Data

Green building ground source heat pump system combines the advantages of green building and ground source heat pump,and has higher design expectations.However,due to many factors such as unreasonable design,unsatisfactory construction and inadequate operation and management,the actual application effect of some projects is not ideal,and it is difficult to achieve the design expectations.At present,the unified and perfect post-evaluation system for the actual operation effect of ground source heat pump in green buildings has not been established,and the application effect of the project is difficult to measure.It is difficult to achieve the horizontal comparison evaluation between different projects and the comprehensive longitudinal comparison evaluation between the actual operation effect and design expectation of the same project.Ground source heat pump system in green building can ensure indoor environment comfort with minimum energy consumption,combining the advantages of low load of the building itself,while relying on fine design,high-performance equipment and high-level operation management.Timely and effective operation control,remarkable energy saving and emission reduction effect and comi’ortable indoor environment are the expected key contents of the design of green building ground source heat pump system,and are also the main characteristics of green building ground source heat pump system which is different from ordinary ground source heat pump system in operation.In the actual operation process,the operation control effect,energy saving and emission reduction effect and indoor environment guarantee effect are the key to reflect the operation quality of green building ground source heat pump.Based on the main evaluation function requirements,including application effect evaluation,system operation optimization guidance and investment decision-making reference,and taking into account the specific evaluation requirements of the characteristics of green building ground source heat pump system,a post-evaluation systel for the application effect(:)f’ green building ground source heat pump system is established(hereinafter referred to as the evaluation system).Based on the principles of goal orientation,comprehensiveness,scientificity and operability,the evaluation system establishes four aspects of technology,energy saving,environmental protection and economy,23 quantitative evaluation indexes,and the index weight is determined by hierarchical-entropy weight method.Through the analysis of the characteristics of evaluation methods,the fuzzy comprehensive evaluation model and grey comprehensive evaluation model are established respectively,and the results of multi-index evaluation are integrated,so as to realize the horizontal comparison and evaluation between the application effects of ground source heat pump systems in different green buildings and the vertical comparison and evaluation of the practical application effects and design expected effects of the same system.The post-evaluation system of application effect of green building ground source heat pump system is used to evaluate the typical case A comprehensively.Case A has a fuzzy comprehensive score of 79.71,and its overall application effect is good.The fuzzy comprehensive scores of technology,energy saving,environmental protection and economy are 77.36,100,77.64 and 80.73,respectively.It shows that the ground source heat pump system has better technology and can ensure indoor environment comfort.Compared with the conventional energy system,the energy consumption of heating and air conditioning system is reduced.At the same time,combined with the low load characteristics of green buildings,the energy saving and emission reduction effect is further improved,and the economy is reasonable.However,the results of grey comprehensive evaluation of practical application effect and design expected effect of the case are 0.58 and 0.8,respectively.It shows that the actual operation effect is different from the actual expected effect.From the detailed analysis of quantitative indicators,the operation control level of indoor environment,heat pump unit and conveying system needs to be further improved.It is suggested that optimization should be carried out in three aspects,including avoiding overheating of heating room temperature and undercooling of cooling room temperature,formulating reasonable operation strategy according to operation characteristics of heating and cooling season system and circulating water flow demand,and increasing temperature difference between inlet and outlet water at user side and source side.