Charles Zimmerman, vice president of Prototypical Design and Construction Standards for Wal-Mart Inc., says more than 2,700 Wal-Mart and Sam’s Club stores have natural-light systems, and that the savings in utilities have been well worth the effort. Also, Wal-Mart was one of the first big box’ers to daylight harvest in a big way.
“We first experimented with this in 1995, in the City of Industry, Calif. — an experimental store we have there –- and we immediately saw the pay-backs associated with it, and in 1996 we made it part of our (construction) prototypes,” Zimmerman says. “Then at some point in 1996, every new store we constructed included the daylight harvesting systems.”
That trend continues to this day. The majority of Wal-Mart Inc.’s systems come from Sacramento-based SunOptics Prismatic Skylights, which also manufactures fully automated solar-lighting systems.
“The store managers and associates love it – and the customers love it,” Zimmerman says. “As the sun rises in the morning and starts emitting light through the skylights, there’s a sensor that reads the amount of natural light coming in and then, via some computer controlled technology, it tells the interior lights how much to dim, up to a point where the electric lights will go completely off. Even as a cloud passes over, the lights will adjust automatically to compensate for that.”
Coming from a bottom-line perspective, Wal-Mart execs say the number one benefit is the energy savings, and Zimmerman notes the company has seen a surprisingly quick return on its investment.
“Now, with the prices we’re paying for the skylight systems compared to typical utility prices, we’re seeing anywhere from a two to four year payback, and that is the number one reason (for going natural). Clearly the lighting looks better and feels better,” Zimmerman concludes.
Though Wal-Mart was an early convert and now has thousands of stores with daylight harvest systems, at least a half-dozen big box retailers have joined the movement over the past decade, not to mention municipalities and government agencies throughout the States.
The Bilbrey brothers themselves have been peddling sunbeams for almost two decades and believe their company set the bar and pioneered the technology and lingo that now pervades the industry.
“We have promoted the terminology of ‘Daylighting’ for 20 years, and it has just been in the last few years that all the people who focus on sustainable solar energy designs have started taking notice,” Bruce Bilbrey says. “We call daylighting ‘the simple solar.’ We don’t convert, revert or divert or store it; with the right components you can use it efficiently, and compared to other solar related technology it’s really simple and relatively cheap.”
The Arizonan points out that retailers are the primary commercial users of simple solar.