Commissioning for optimal savings from daylight controls

Minneapolis Central Library - interiorProper commissioning can lead to energy savings—often 60% or more

Daylighting control, or daylight harvesting, has become a common energy savings strategy in many sustainable building projects, but several barriers still prevent successful implementation of this strategy in mainstream construction. Considerable effort is expended in the architectural and lighting design of daylighting controls, with actual execution being an afterthought.

Best practices suggest that a significant commissioning effort is required for daylighting controls to function properly and reach full energy savings potential. While HVAC systems often receive significant attention at this stage, lighting controls and most specifically daylighting controls, generally do not.

This project provided the opportunity to measure, analyze and demonstrate the importance of commissioning daylighting systems, with specific focus on the calibration and functional testing aspect of commissioning. Our goal was to determine the level of success being achieved, the amount of energy savings realized and the missed opportunities for additional energy savings.

Acknowledgements

The project was a result of grant support from the Minnesota Department of Commerce, Division of Energy Resources (funded by Minnesota ratepayers). The cooperation of Division staff is also appreciated.

Other Energy Center staff who contributed to this project include Mark Vincent, Dan Cautley, and Tom Holaday. Staff from Lutron Electronics also generously assisted with the commissioning step for Lutron control systems; contractors assisted in commissioning of other systems. The project also benefitted greatly from the time and effort of each of the building managers and engineers at the sites we studied. Thank you to all who participated.