Life-cycle environmental assessment of energy-retrofit strategies on a campus scale

摘要

The aim of this study is to determine the life-cycle environmental impacts associated with energy-retrofit strategies on an urban scale. A prototype campus model that includes deep retrofit clusters, moderate retrofit clusters, and baseline retrofit clusters is used as a case study. The retrofit strategies included major changes to the building envelope with additional insulation, replacement of exterior windows and doors, shading, primary mechanical system replacement, and lighting system replacement. The study aims to (1) compare the three levels of energy retrofit against the existing condition to determine potential reductions in environmental impact, (2) identify the life-cycle hotspots of the energy-retrofit strategies and possible mitigation methods, (3) calculate the payback time for each energy-retrofit level, and (4) demonstrate an example of how life-cycle assessment (LCA) could be used as a quantitative assessment method for energy retrofits done on a large scale. The life-cycle environmental impact is calculated for five categories. The results indicate that energy retrofits overall have a positive effect in terms of reducing life-cycle environmental impacts in all environmental categories except ozone-depletion potential. The deep energy retrofit has a much shorter payback time for its environmental-impact reduction than the other energy-retrofit levels.