B2._ Building tuneups
Retro-commissioning a building tests and adjusts its energy systems and maintenance procedures to meet the original design intent and/or optimize them to satisfy current operational needs. (See also B4_ Building Commissioning.)
PNNL’s “A Guide to Building Commissioning” gives an overview of the process, and Chapter 7 of the DOE’s “Operations & Maintenance Best Practices: A Guide to Achieving Operational Efficiency” discusses details and the savings demonstrated by research. The EPA estimates that commercial buildings have a median retrocommissioning cost of $0.27 per square foot, energy savings of 15%, and a simple payback of just eight to nine months.
Seattle requires a recommissioning process (called a building tune-up) every five years for commercial buildings over 50,000 square feet.
PSE offers building tune-up incentives for buildings over 50,000 sq ft. – $5,000 for completion of the process, and a performance incentive of $0.05/kWh and $0.80/therm for sustained reductions in energy use over the next year.
New York City’s Local Law 87 requires buildings larger than 50,000 square feet to be retro-commissioned once every ten years, in addition to having an energy audit.