Evaluation And Result Analysis Of Building Energy Efficiency Of A Hospital In Hefei

Building energy conservation is an important way to realize national energy strategy,improve energy structure,reduce total energy consumption and implement sustainable development.Building energy efficiency labeling is the booster of building energy conservation.In 2008,China formulated the technical guidelines for civil building energy efficiency assessment labeling.The evaluation index of building energy efficiency is divided into basic item,stipulation item and selection item.Among them,the basic item and the specified item are combined with the current energy saving standard.The basic item is the energy consumed by the heating and air conditioning unit area of the building calculated according to the requirements and methods of the energy saving standard.The specified item is the item that the system must meet.Evaluation methods include software evaluation,document review,field inspection and performance testing.For general residential and public buildings,assessment institutions of building energy efficiency label mainly make qualitative assessment based on design,construction,completion acceptance and other data,and give relevant conclusions through software calculation.For large public buildings,on the basis of the above work,the building energy efficiency evaluation institutions can only give relevant conclusions after selective detection of the main aspects affecting the building energy efficiency.To carry out energy efficiency evaluation is the basis to test the efficiency of energy system and the energy consumption of buildings.This paper is mainly divided into the following parts to study and analyze energy efficiency evaluation:Firstly,this paper describes the general situation of this project and the general situation of energy use system.The third chapter calculates the theoretical value of energy efficiency evaluation.Pkpm-eep software was used to simulate the energy consumption,and the relative energy saving rate of the tested building was 5.24%,meeting the requirement of one-star energy saving rate.The fourth chapter reviews the documents,calculates and analyzes the contents of the13 items in the energy efficiency evaluation.Infrared thermal imager was used to test the thermal bridge.The heat and electricity consumption ratio of some water pumps and the power consumption per unit air volume of the fans in the cold and heat source and air-conditioning system are calculated and analyzed.The rest shall be judged by means ofdocument review and on-site inspection.The results show that all the items in the 13 items meet the requirements.The fifth chapter mainly tests and analyzes the content of the selected items in the energy efficiency evaluation,and the selected items score 50 points in total: the field test and analysis and calculation of the solar hot water system are carried out,and the results show that the solar guarantee rate of this project is more than 50%,meeting the score requirements.According to the simulation report,natural ventilation and natural lighting were optimized.The all-air system can adjust the fresh air ratio,and operate with fresh air in transition seasons.The fresh air system is equipped with fresh air valve in transition seasons,and adopts all-fresh air operation mode in transition seasons to save energy consumption of air conditioning.Variable flow system is adopted in the water system of air conditioning,and variable frequency pump is adopted in the cold and hot water circulation pump of air conditioning.The pressure difference bypass control valve is set between the water concentrators to control the temperature difference between water supply and return.Two 1500-ton double-duty chillers(one for use and one for standby)were used for cold water storage at night.Except for the four-floor inspection department which adopts direct flow air conditioning system,the other fresh air conditioning units adopt heat pipe heat recovery to recover part of exhaust air energy.The energy consumption of building air conditioning system and lighting can be measured and counted by item and region.In winter,the cooling tower is used for free cooling,and the demand for free cooling in winter is met through the plate exchange of two double-working cooling towers(the cooling tower is equipped with electric heat tracing anti-freezing measures).Finally,according to the actual situation of the project,it is suggested to set up solar pv on the roof of the west gate clinic building and recover the condensation heat of the air conditioner to improve the energy saving performance of the system and improve the level of the building sign.