Lifecycle Assessment of Beijing-Area Building Energy Use and Emissions: Summary Findings andPolicy Applications
Buildings are at the locus of three trends driving China's increased energy use andemissions: urbanization, growing personal consumption, and surging heavy industrialproduction. Migration to cities and urban growth create demand for new buildingconstruction. Higher levels of per-capita income and consumption drive buildingoperational energy use with demand for higher intensity lighting, thermal comfort, andplug-load power. Demand for new buildings, infrastructure, and electricity requiresheavy industrial production. In order to highlight one key implication of China'songoing urbanization, rising personal consumption, and booming heavy industrialsector, this study presents a lifecycle assessment (LCA) of the energy use and carbonemissions related to residential and commercial buildings. The purpose of the LCAmodel is to quantify the impact of a given building and identify policy linkages tomitigate energy demand and emissions growth related to China's new buildingconstruction.
Results of the residential and commercial building LCA model case study analysisshow that building operations account for on average 80% of energy use and relatedemissions while building materials comprise almost 20%, with maintenance,construction, and demolition covering the remaining small portions of the total lifetimeenergy and emissions. Commercial buildings are more material and energy intensivethan similarly-sized residential buildings. However, the wide range of energy andmaterial intensity values among the ten Beijing-area buildings used in this studysuggests that particular building's lifecycle energy use and emissions are highlysituation specific.
The most useful potential policy application of the residential and commercial buildingLCA models is for comparative analysis beyond the Beijing case studies analyzed in thisstudy. Scenario analysis can be used for benchmarking and identification of policypriorities. The LCA approach allows policy makers to add an embodied energydimension to new codes uses to incentivize construction of zero energy buildings.Another policy application would be to use the models to help develop bottom-upemissions inventories, in which case it would be important to disaggregate energy usedata for more accurate emissions modeling. The LBNL building LCA modelsdeveloped in this study were limited by incomplete local input data; however they canserve as an indicator of potential policy-linked LCA model development. Dependingon the type of LCA model policy integration, it may be useful to incorporate occupancydata for per-capita results. On the question of density and efficiency, it may also beuseful to integrate an explicit spatial scaling mechanism for modeling neighborhoodand city-level energy use and emissions.