Energy System Evaluation Of Near Zero Energy Consumption Residential Buildings In Cold Region

Due to the severe energy environment of our country,technology research and application of energy-saving buildings are inevitable trend in the future.The concept "low energy consumption building" and "near zero energy building"(expressed in n ZEB in the following)have been frequently encountered in the research of architecture in recent years.n ZEB have many advantages,such as high insulation performance,doors and windows with good air tightness,refined indoor environment regulation,efficient energy system,etc.Quite a number of research papers have been published in the field of simulation and demonstration project of n ZEB since 2016.Domestic research of low energy consumption building,n ZEB will be one of hot topics in the construction field for a long time to come.This paper reviews the development history of n ZEB and its research status domestic and overseas,summarizes its energy system.Based on the existing research,selects a low-rise residential building in Dalian as a research object,builds a building model on TRNSYS platform and carry out annual load simulation of n ZEB.Then,according to annual load distribution characteristics of n ZEB,its control system is designed.The system including yearly,weekly,daily control of indoor environment setting temperature,and start-stop control,frequency control of fresh air units,indoor end,circulatory system,heat pump units.Compare energy results with control scheme optimization with results of non-refined control and the conclusion can be drawn: control scheme optimization can save more than 10% of the total energy consumption in n ZEB.The underground shallow burying tube experiment platform was built before evaluating energy system.This experiment verifies the simulation accuracy of software.Meanwhile it studies the effects of various factors on heat flooding and releasing of buried pipes in soil.Those factors including buried pipe form,circulating water temperature,flow,groundwater seepage,etc.Finally,this paper evaluates the energy system based on the previous research results.Take four energy systems whose domestic application is more extensive and suitable for newarchitectural features as the research object.AHP-entropy weighting method is used to evaluate the energy system of n ZEB in economy,energy and environment.The conclusion is that for n ZEB in cold region adopting ground source heat pump system with vertical buried pipe is more conducive to reducing building energy consumption,protecting ecological environment and saving economic investment.