Value Beyond Cost Savings - Green Building Finance Consortium

Value Beyond Cost Savings: How to Underwrite Sustainable Propertiesf. CommissioningCommissioning (Cx) is the process of ensuring that systems are designed, installed,functionally tested, and capable of being operated and maintained to perform in conformitywith the design intent. 18 Commissioning can be done for new buildings, new acquisitions,and on an ongoing basis in existing buildings.Commissioning for existing buildings (sometimes referred to as retro-commissioning) is asystematic process for investigating, analyzing, and optimizing the performance of buildingsystems by improving their operation and maintenance to ensure their continuedperformance over time. This process helps make the building systems perform interactivelyto meet the owner’s current facility requirements. 19The value of commissioning was confirmed in a July 2009 study by Evan Mills: “BuildingCommissioning: A Golden Opportunity for Reducing Energy Costs and Greenhouse GasEmissions”. Based on data from 37 commissioning providers representing 643 buildingscomprising 99 million sq. ft. of floor space from 26 states, the study reported the followingkey findings for commissioning:• Median commissioning costs: $0.30 and $1.16 per square foot for existingbuildings and new construction, respectively (and 0.4% of total construction costsfor new buildings).• Median whole-building energy savings: 16% (existing) and 13% (new).• Median payback times: 1.1 (existing) and 4.2 years (new).• Median benefit-cost ratios: 4.5 years (existing) and 1.1 years (new).• Cash-on-cash returns: 91% (existing) and 23% (new).• Projects employing a comprehensive approach to commissioning attained nearlytwice the overall median level of savings.• Non-energy benefits are extensive and often offset part or all of thecommissioning cost.Carnegie Mellon also reports positive findings on commissioning:• CMU’s BIDS has identified seven retro-commissioning case studies indicatingan average annual savings of 8.1% in total building energy consumption. Theseseven studies demonstrate that retro commissioning results in annual energy costsavings of approximately $0.15 per square foot.18 “Design Briefs: Building Commissioning,” Energy Design Resources (http://www.energydesignresources.com/)19 Building Commissioning Association (http://www.bcxa.org/)45