Green Building Performance. Reuse vs Recycle.
Another talk for the quantitatively-inclined at the recent US Federal Environmental Symposium East was “Results of LEED Building Energy Performance Study” by Brendan Owens of the US Green Building Council (USGBC). LEED is a rating system for buildings in terms of their environmental impact administered by the USGBC. A building can earn points within the system for energy and resource efficiency, use of renewable materials, recycling, diversion of construction waste from landfill, etc.
The talk concerned an interesting study commissioned by the USGBC and completed by the New Building Institute. The key question was how did buildings that received LEED certification when they were completed, perform once they were in operation. 121 certified buildings, representing 22% of the total number, participated in the study. (Note: these were the ones who responded to an invitation, sent to all, to participate in the study, and so do not form a random sample.) The results were that in general, LEED buildings were 25-30% more energy efficient than non-LEED buildings. The data were pretty variable and unpredictable (e.g. some very highly rated buildings performed near the bottom). It seemed like some of the variability could have been mitigated by controlling for building type within the study. Buildings serve different functions. A data center is going to have a different energy use profile than an office building. The results are being used to shape the next version of the LEED rating system. The study is available here.
All told, the symposium showcased many good initiatives and programs. One thing that seemed to be lacking, however, was something along the lines of the cradle-to-cradle viewpoint, with a more critical take on recycling, for instance, and more emphasis on avoiding many of these problems at the outset by more thoughtful design and reuse. There was some evidence of this, as in a different USPS talk about how the amount of hazardous materials they generate has been cut by 90% through green purchasing. But in other cases, recycling programs and green electronics purchases were trumpeted with far less said about reusable over recycled items (such as bottles) and upgrading equipment versus purchasing new environmentally-friendly equipment (like computers). Nevertheless, many steps in the right direction are being taken.