Commissioning of energy-efficiency measures: Costs and benefits for 16 buildings

Abstract

IV V assume that once commissioned, the EEM saved 100 percent of the design estimate, plus additional savings from correcting deficiencies that were not related to the EEMs. Under these assumptions the average and median simple payback times are 9.6 and 9.9 years. These results a r e dominated by the economics of the EEMs. The economics are sensitive to the assumption of how long the savings persist. The cost-benefit analysis of commissioning as a' stand-alone measure showed that benefits are greater than the costs for six of the 16 buildings for the low lifetime scenario. Under the high lifetime case the benefits are greater than the costs at ten of the 16 sites. When considering the costs and benefits of commissioning and the EEMs combined, the benefits exceed the costs for ten buildings for both the low and high lifetime case. Implications This study has shown that for most buildings, the investment in commissioning was cost effective based on energy savings alone. Energy prices are low in the Pacific Northwest, and the cost-effectiveness would be higher in other regions of the U.S. The findings are subject to significant uncertainty because of the small sample size and lack of metered data in the evaluation; additional case study analysis i s needed. However, the finding suggests that utility sponsored commissioning should be considered in demand-side management activities. In an era when utilities and energy providers are positioning themselves for a deregulated energy marketplace, companies that offer performance ce assurance and commissioning are likely to be at a n advantage because of, their more direct involvement in understanding and addressing customer's needs. Building owners want buildings that work as intended, are comfortable, healthy, and efficient. Looking beyond energy savings benefits, it is likely that the non-energy benefits outweighed the'costs at the several of the sites. The owners are generally not well informed, however, about the benefits of commissioning. The distinction between EEM and whole-building commissioning was blurred, especially among the large buildings. This suggests the need to commission not only the most energy-saving EEMs, but the most energy-consuming building systems: Greater use of metering, Energy-Management and Control System trend-logs, and enhanced links to O&M will help improve the effectiveness of commissioning by increasing the ability to evaluate its value and ensure persistence.of savings from deficiency corrections. vi *