Research On The Fourth Step Energy Efficiency Index System For Residential Buildings In Heilongjiang Province

In order to promote the goal of energy conservation of residential buildings in Heilongjiang Province,the provincial energy conservation standard preparation team summarized the practical experience of building energy conservation in Heilongjiang Province,and made the fourth step energy conservation standard of Heilongjiang Province by referring to the advanced energy conservation standards.In order to further promote the energy conservation of residential buildings in Heilongjiang Province,it is of great significance to study the limit value of the fourth step energy conservation standard compilation technical indicators in Heilongjiang Province.The author has participated in the research work of the revised contents of the compilation group.In this paper,the theoretical verification process of the limits,provisions and calculation methods of the standard will be summarized.First of all,through investigation and market research,the feasibility of Heilongjiang Province to formulate the fourth step of energy saving target is determined.The fourth step energy saving standard of Heilongjiang Province is 30% compared with the third step.Through the investigation and calculation of boiler efficiency and pipe network transmission efficiency,the fourth step energy saving of heating system is 6.7% and building energy saving is 25%.Taking the multi-storey building in Harbin as an example,the total energy saving rate and the building energy saving rate are calculated.At the same time,the fourth step energy-saving building heat consumption index limits of other typical cities in Heilongjiang Province are calculated,and the overall fourth step energy-saving total energy-saving rate and building energy-saving rate of Heilongjiang Province are obtained.Secondly,using De ST-h to establish the calculation model of the solar radiation heat gain of the external window and make dynamic time-by-time analysis to explore the influence of shading coefficient,orientation and heat transfer coefficient on the energy saving of the external window.It is found that the solar radiation heat gain of each month during the heating period of the south facing window is about 4-6 times of that of the north facing window.Increasing the sun shading coefficient will increase the solar radiation heat gain of the south facing window,and the effect of the south facing window is more significant.When selecting the external window,the sunshadecoefficient and heat transfer coefficient should be considered comprehensively.It is suggested to add the limit value requirements of the sunshade coefficient of the external window in the process of compiling the standard.Thirdly,according to the fourth step of the calculation of energy-saving rate and compare a variety of energy-saving schemes,the calculation of the fourth step of the energy-saving standard in the cold zone B of the outer envelope structure is more reasonable index limit.It is suggested that the limit value of heat transfer coefficient is 0.35 W /(m2 k)for external wall,1.6W /(m2 k)for external window and 0.22 W /(m2 k)for roof.As the actual energy-saving rate used in this calculation is less than 75%,in order to reduce the energy-saving rate,the national standard and provincial standard reduce the heat transfer coefficient limit value of the roof part with great energy-saving potential.At the same time,the fourth step of the provincial energy-saving standard finally decides to unify the limit value requirements for severe cold areas a and B in the province,so the recommended limit value of the heat transfer coefficient of the roof is slightly higher than the final limit value of the standard.Finally,using dynamic simulation software and steady-state calculation method to calculate the building heat consumption indexes of 18 typical cities in Heilongjiang Province,the error of the heat consumption indexes obtained by the two methods is within the acceptable range,which verifies that the steady-state calculation results of Heilongjiang Province are also more accurate,and the steady-state calculation method can be used as the index calculation method in the energy-saving standard.