Life-cycle energy analysis of prefabricated building components: an input-output-based hybrid model

As an effective strategy for improving the productivity of the construction industry, prefabricated construction has attracted concerns worldwide. This study investigated the life-cycle energy use of prefabricated components and the corresponding effect on the total embodied energy use for a number of real building projects. Result showed that the life-cycle energy use of prefabricated components ranged from 7.33 GJ/m3 for precast staircase to 13.34 GJ/m3 for precast form. The recycling process could achieve 16%-24% energy reduction. This study also found that apart from reusability, energy savings are also obtained from waste reduction and high quality control, saving 4%-14% of the total life-cycle energy consumption. All these advantages can be regarded as important environment friendly strategies provided by precast construction. The linear regression analysis indicated that the average increment in energy use was nearly linearly correlated with prefabrication rate. Precast facade and form are identified as energy-intensive components compared with the conventional construction method. Therefore, the challenge lies in improving the integrality and quality of the prefabrication technique while reducing its dependence on energy-intensive materials. Besides, attention should be focused on improving the maturity of the precast market to avoid additional energy consumption during prophase investigation.