Success of Commercial Building Retuning in Federal Buildings: Results and Case Studies

AbstractRetuning is a form of scaled-down retrocomissioning for commercial buildings that targets low- and no-cost control changes to building automation systems (BASs) to achieve immediate energy savings. A retrospective analysis of retuning for a set of 26 federal office buildings and courthouses is presented, detailing the retuning process that was employed, the types of retuning measures that were commonly implemented, the most effective of those measures, and the energy and cost savings achieved as a result of the process. The buildings that participated in these retuning efforts were benchmarked as having, on average, very efficient baselines. However, these buildings achieved, on average, 12.1% annual energy savings as a result of the retuning efforts, with an associated cost savings of $1.62/year per square meter ($0.151/year per ft2) of floor space. Several key factors that are observed to promote successful retuning outcomes are discussed as well.