Advancing Green Building Rating Systems Using Life-Cycle Assessment

by Sami G Al-Ghamdi

Institution: University of Pittsburgh
Year: 2016
Posted: 02/05/2017
Record ID: 2078828
Full text PDF: http://d-scholarship.pitt.edu/26317/4/alghamdisg_etd2015.pdf


The aim of this research was to quantitatively analyze the potential ability of life cycle assessment (LCA) in combination with green building rating systems (GBRS), such as Leadership in Energy and Environmental Design (LEED), to reduce a building’s environmental impacts, considering variations in climate, renewables, energy sources and economic aspects. First, international variations in the energy use and associated environmental life cycle impacts were investigated. A reference Building Information Model (BIM) office building was developed and placed in 400 locations with changes to meet energy standards. LCA was then performed on all the buildings’ energy consumption. The results varied considerably between the U.S. (394 ton CO2 eq) and international (911 ton CO2 eq) locations. Since GBRS are expanding internationally, energy source considerations for buildings should be considered with a particular suggestion of targeted goals reductions versus aggregated certifications. Second, the BIM and LCA models were extended to include on-site renewable energy (wind and solar) and located in 25 locations around the world. An LCA and LCCA were performed to consider different energy sources including renewables and associated prices at each site. Environmental impacts and economics varied dramatically. The requirements of renewable energy generation in existing GBRS need to be developed and changed to be a percentage of what is actually available on-site, instead of a fixed percentage of the building’s energy. Third, a comparative analysis was conducted for three whole-building LCA tools available today. The software tools vary in key aspects such as intended users, design stage, and time. One of the most important challenges is a comparison with a baseline. The results indicate that given the same building, the LCA results varied by about 10% in the pre-occupancy impact to 17% in the operational impact. This reinforces the need to not only refine LCA methods for GBRS, but also work towards robust data sets for building systems and products. At a minimum, GBRS should include LCA uncertainty analysis into their systems.