How Low Can You Go?
> Compaq Computer's facilities manager saved the company about $1 million a year by cutting back on energy use. By increasing daylighting in the building along with other improvements, worker productivity increased by 55 percent in just one year.
(Sustainable Development International Corp. website, www.smartoffice.com, 2002)
> The ING Bank, in the Netherlands, built a new headquarters designed to favor natural lighting. Since opening in 1987, the bank has used 92 percent less energy than an adjacent bank constructed at the same time, saving the bank $2.9 million a year.
(Charleston Gazette, March 12, 2000)
> The U.S. Department of Energy's (DOE) Federal Energy Management Program reports that daylighting can significantly cut lighting energy use for lighting building interiors, sometimes by up to 75 or 80 percent The DOEís Renewable Energy Laboratory's Thermal Test Facility in Golden, Colorado, was designed to provide natural lighting allowing it to use 75 percent less energy for lighting than a building without daylighting features. Except for the central service area, the facility is entirely daylit, which has also decreased the energy load imposed on the buildings mechanical cooling system. The DOE reports that for many commercial buildings, the total energy costs can be reduced by as much as one-third through the optimal use of daylighting strategies.
(Federal Energy Management Program Newsletter, March/April 2002)
> The Florida Energy Conservation Assistance Program reported that 29 Florida businesses that installed daylighting systems reduced daytime electric lighting consumption by an avenge of 93 percent while still achieving an avenge of 160 foot candles of light with a color rendering index of 98 in work areas.
(Environmental Design & Construction, January 2001)
> From the U.S. Green Building Councilís Sustainable Building Technical Manual, well-designed daylighting project can reduce lighting energy use by 50 percent to 80 percent.
(Environmental Design & Construction, Jan 2001)
> The Wisconsin Daylighting Collaborative found about 86 percent of electricity in traditional buildings goes for light, fans and cooling. A cool daylighting project can cut these costs by more than 50 percent by reducing electric lighting, because daylight produces less heat per unit of illumination than most light sources. The Collaborative also notes that the demand savings are more important than the energy savings since daylighting provides energy usage reduction at the most important time, during peak bows, when energy rates are the highest and daylight availability is the greatest.
(Energy User News, April 2001)