Energy Saving Effect Of Thermal Insulation Walls For Residential Buildings In Hot Summer And Cold Winter Zone

Outside wall insulation has been proved energy-efficiency in the north of China for residential buildings, but the energy-saving effect is less than ideal in hot summer and cold winter zone. The difference of energy use mode in two areas make this happens. To find the suitable wall insulation system, the characteristics of the area should be considered.A room of a residential buildings in Hangzhou is used as the typical analyzing model to calculate the cold consumption of baseline, self-insulation, outside insulation and insulation wall for a single use in summer under three conditions to illustrate the energy-saving effect of hot summer and cold winter zone. The matlab software is used with the numerical calculation method to give the results. It turns out that self-insulation and inside insulation wall can save the energy, and outside insulation wall is of little use. The consist of the energy consumption shows that wall heat storage influence the energy consumption a lot, which also explain the reason why energy saving effect of outside insulation wall is so different in the north and south.A test is conducted on a small-scale model to compare the energy-saving effect between outside insulation and inside insulation wall, and it is also compared with the theoretical relationship, which shows that inside insulation saves more energy bothe in the test and the theory. In addition, a large-scale model is made to give the quantitative analysis to confirm the error between the theoretical and measured values, which also shows the correctness of the theory.Besides the time of single use. the whole energy using season is taken into consideration to see the energy-saving effect of three walls. Base on the fact that outside wall insulation make the initial temperature of room is lower than others, that outside insulation wall can play an energy-saving effect, but it still consume more energy than others unless the temperature difference is larger than5℃.In a single use of8hours, the thickness barely influence the energy consumption between140mm-300mm. And when window-wall ratio get increased, the energy consumption of baseline and outside insulation wall decrease and self-insulation and outside insulation wall increase. The reduction rate is more obvious than growth rate. Both the thickness of walls and window-wall ratio doesn’t change the pros and cons of walls.