Study On Energy-saving Adaptability Of Country House In Guanzhong Area

At present,China is in a phase of rapid construction and development,and building energy consumption is on a long-term growth trend.The"2030 Carbon Peak,2060 Carbon Neutral"has put forward higher requirements for building energy efficiency.Compared to the standardised and orderly promotion of energy efficiency in urban buildings,the energy efficiency work in agricultural buildings,which are still mainly self-built,is progressing slowly and solving the problem of energy consumption in agricultural buildings is a priority.The Guanzhong region is located in central Shaanxi and is a cold region with cold winters and hot summers.For climatic and economic reasons,Energy-saving work in farm buildings has not been easy to implement.The demand for heating and cooling has created energy problems as well as greatly increased the financial pressure on farmers.In order to address the problem of slow progress in regulating energy efficiency and the high energy consumption of farm buildings in the Guanzhong region,this paper examines the following aspects.Firstly,field research was carried out in 22 country houses in the Guanzhong region(five cities and one district),using questionnaires to obtain information on the basic overview of country houses in the Guanzhong region,forms of heating and cooling,economic conditions,indoor thermal comfort,renewable energy and local building materials.Based on the numerous research in the Guanzhong region,typical country house forms were identified and the thermal environment parameters of indoor temperature,humidity,wall temperature and wind speed were tested for typical country houses in winter and summer,Provide a basis for follow-up research.Secondly,through field tests and De ST energy consumption software simulations,it was found that the typical country house had a poor indoor thermal environment and high energy consumption,which was much higher than the energy consumption targets specified in the Energy Conservation Design Standards for Rural Residential Buildings.For higher goals,the energy consumption target per unit area of the typical country house in the Guanzhong region was formulated to be 107.2 k W·h/m~2based on the typical country house,and a higher energy saving target of 75.04 k W·h/m~2(for energy-saving country houses)was proposed based on the step-by-step strategy for energy saving in urban buildings.and 52.53 k W·h/m~2(low-energy country house).The impact of a single factor on the energy consumption of farm buildings in the Guanzhong region was investigated on the basis of heat transfer coefficients,and five influential factors(heat transfer coefficient of external walls,heat transfer coefficient of roofs,heat transfer coefficient of external windows,north-facing window-to-wall ratio,and building height)were identified as having a significant impact on the energy consumption of country house.Using the energy consumption per unit area as an indicator,the multi-factor orthogonal experiment was used to derive the energy consumption simulation results and the sensitivity ranking of the influencing factors.Third,based on the multi-factor orthogonal experiments,the adaptability of the regulated farm buildings in the Guanzhong region was explored.It was found that test scenario 47(heat transfer coefficient K=0.25 W/(m~2.k)for external walls,K=0.85 W/(m~2.k)for roofs,K=3.2W/(m~2.k)for external windows,a ratio of 0.45 for south-facing window walls and 0.35 for north-facing window walls,and a building height of 2.9m)was more economical than the code country house in terms of energy consumption per unit area when it was basically the same as the representative country house.It is more economical than the code standard,and then in-depth comparison of the economics and thermal optimisation practices of Test Scheme47 and the code standard country house.The results show that Trial Scheme 47 is more suitable for the Guanzhong region than the Code.It also explores the economics and investment priorities of new country houses and the economics and retrofit priorities of existing country houses under the code country house index,and gives country house residents a simple and clear menu of step-by-step retrofit recommendations based on the needs of different residents.Fourth,on the goal of energy efficient farm buildings in the Guanzhong region.The same approach was used to determine the thermal performance practices and economics of the envelope based on the representative country house,narrowing down the influencing factors horizontal working conditions.Test scheme 71(heat transfer coefficient K=0.25 W/(m~2.k)for external walls,K=K=0.85 W/(m~2.k)for roofs,K=2 W/(m~2.k)for external windows,a ratio of 0.45 for south-facing window walls and 0.15 for north-facing window walls,and a building height of 3m)was found to be more suitable for the energy efficiency standards for energy-efficient country houses in the Guanzhong region,and a step-by-step renovation menu under the energy-saving farm house standard.Finally,based on the target of low-energy country houses in the Guanzhong region,the scheme design for low-energy country houses was determined based on a combination of the50th test scheme and the scheme under the code energy efficiency standard,together with a passive sunspaces suitable for the Guanzhong region.It also identifies the economics and prioritises the influencing factors for new and existing country houses under the corresponding standards,and gives a corresponding step-by-step retrofit menu according to the needs of different residents.The above research provides residents in the Guanzhong area with economic adaptability solutions that meet the norms and standards and energy-saving design solutions with higher energy-saving goals,and provides theoretical and technical requirements for the steady and orderly recommendation of farm house energy-saving work in the Guanzhong Regions.