Daylight harvesting takes advantage of available daylight to augment electric lighting systems. Dimming ballasts and photoreceptors can reduce electric lighting loads proportional to the amount of daylight that enters the space. The more usable daylight entering the space, the more the electric lights can be dimmed, resulting in significant energy savings—as much as 60 percent of the connected lighting load to the space. [IES, 1993]
Laboratory lighting designers will find that open ballroom-type areas and large offices that have sufficient daylight are the most cost-effective areas for daylight harvesting. Small offices with only one or two fluorescent fixtures, viewed individually, are usually not cost-effective areas for daylighting. However, if an entire laboratory lighting system is viewed as a whole, daylight harvesting in several small spaces may add up to be cost effective.
