Study Of Building Life-cycle Energy Use And Relevant Environmental Impacts

Building energy use has been raising more and more concerns in China on the field of energy consumption as well as environmental degradation. Researches related with building life-cycle energy use were started in the late 1990s. Researchers of west-Europe, north-America and Oceania had applied this study into many cases and generated lots of useful outcomes, but there are nothing had been systematically done in China. Study of building life-cycle energy use is helpful to understand the overall level and the characteristics of Chinese building energy consumption, to accumulate basic data on building energy use and to assess relevant environmental impacts. It can provide a more comprehensive, systematic and long-term view for researchers on building energy use. By conducting such researches, much more comprehensive and sophisticated understandings and strategies dealing with environmental impacts araised by building energy use can be expected.Based on the analysis of current energy and environmental chanllenges that China is confronting, the study applied Life-cycle theory into the research of building energy use. This research established numerical models to estimate building life-cycle energy use from both macro and micro level, and further applied those models to evaluate Chinese overall building life-cycle energy use and two domestic buildings of different type in Beijing as examples. The research revealed that: the total amount of the building life-cycle energy use in China hits 576.16 Mtce, account for 44.1% of total energy comsuption in China in 2000, which is much higher thanthe conventional perception; building A (main structure is made of bricks and concrete) consumes 156249.99 GJ and 30.94 GJ/m2 through all its life, building B (main structure is made of concrete) consumes 819847.99 GJ and 30.69 GJ/m2 through all its life. Based on these findings and conclusions, the author further estimated the annual environmental emission related with the building life-cycle energy use in 2000: CO2 320.19 Mt (coal equivalent), CH4 6840.4 Kt, SO2 7821.8 Kt, NOX 5873.9 Kt and soot 3597.6 Kt, accounting for 36.0%, 16.0%, 39.2%, 29.5% and 30.9% of the total nation emission level respectively.Based on the tendency and characteristics of energy use of each life stage reflected from the model results, conclusion of the worsening of environmental impacts araised from building life-cycle energy use can be deduced. These environmental impacts will be endowed some new features, which need to be alleviated via new environmental stretagies. The study calls for whole life-cycle energy conservation in order to cease the tendency of increasing energy consumption and worsening of the environment, policy instruments on each building life stage such as energy saving in construction material industry, building energy efficiency design, transportation energy conservation, recycle and reuse the construction wastes and the building life-cycle design are all necessary to reach a more sustainable building life-cycle energy use.