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The Cost-Effectiveness of Commissioning New and Existing Commercial Buildings: Lessons from 224 Buildings

Authors:
  • Lawrence Berkeley National Laboratory (Retiree Affiliate)

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Synopsis Scattered case studies and anecdotal information form the "conventional wisdom" that building commissioning is highly cost-effective. Given that this belief has not been systematically or comprehensively documented, it is perhaps of no surprise that the most frequently cited barrier to widespread use of commissioning is decision-makers' lack of information pertaining to costs and associated savings. Designed as a "meta-analysis," this paper compiles and synthesizes published and unpublished data from real-world commissioning and retro-commissioning projects, establishing the largest available collection of standardized information on new and existing building commissioning experience in actual buildings. We analyze results from 224 buildings, representing 30.4 million square feet of commissioned space, across 21 states. We developed a detailed and uniform methodology for characterizing the results of projects and normalizing the data to maximize inter-comparisons. For the commissioning of existing buildings, we found median energy cost savings of 15% [7% to 29% interquartile range, i.e. 25th to 75th percentiles] or $0.27/ft 2 -year, and median payback times of 0.7 years [0.2 to 1.7 years]. For new buildings, median commissioning costs were 0.6% [0.3% to 0.9%] of total construction costs or($1.00/ft 2), yielding a median payback time of 4.8 years [1.2 to 16.6 years]. These results exclude non-energy impacts. When non-energy impacts are included cost-effectiveness increases considerably, and the net cost for new buildings is often zero or even negative. Cost-effective results occur across a range of building types, sizes and pre-commissioning energy intensities.
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The Cost-Effectiveness of Commercial-Buildings Commissioning: A Meta-Analysis of Energy and Non-Energy Impacts in Existing Buildings and New Construction in the United States Creating California's Online Commissioning Case Study Database: Case Studies Go High Tech
  • E Mills
  • H Friedman
  • T Powell
  • N Bourassa
  • D Claridge
  • T Haasl
  • M A Piette
  • H Friedman
  • T K Haasl
  • Gillespie
Mills, E., H. Friedman, T. Powell, N. Bourassa, D. Claridge, T. Haasl, and M.A. Piette. 2004. "The Cost-Effectiveness of Commercial-Buildings Commissioning: A Meta-Analysis of Energy and Non-Energy Impacts in Existing Buildings and New Construction in the United States." Lawrence Berkeley National Laboratory Report No. 56637 http://eetd.lbl.gov/emills/PUBS/Cx-Costs-Benefits.html Friedman, H., T. Haasl. K. Gillespie. 2004. " Creating California's Online Commissioning Case Study Database: Case Studies Go High Tech. " Proceedings of the 2004 ACEEE Summer Study on Energy Efficiency in Buildings.