That’s not to say that the building owner has to adopt a “money is no object” attitude toward lighting controls. Even for owners that identify energy savings as a project priority, first costs remain an important issue. That was the case in the construction of the Wal-Mart in City of Industry, Calif. Wal-Mart designated the facility as an Environmental Demonstration Store that could educate the public by example about the benefits of energy-efficient technologies and environmental issues. To that end, the goal of the project was to use an integrated design that beat California’s Title 24 energy standard by at least 25 percent. To achieve that goal, Wal-Mart was open to the use of controlled lighting, but the company wanted to be sure the design was cost-effective.

A collaborative design effort was the key to meeting energy and first-cost goals. Daylighting was a critical element of the design, which used special skylights and continuous dimming controls to respond automatically to daylight levels.

Testing conducted by the team showed that substantially less lighting was needed at night than was normally used. And the team found other savings that could help offset the investment in energy-efficient technologies. For example, the team determined that a drop ceiling wasn’t a necessity; removing it from the design saved $68,000.

How did the lighting design measure up at the bottom line? Lighting energy was cut by 47 percent from Title 24 requirements for 24-hour operation. Payback is estimated at less than three and a half years, excluding the photovoltaic panels used on the project.

Another reason that building owner involvement is crucial is that the owner has to live with the lighting controls. If the controls aren’t well-designed and properly adjusted, occupants may override or disable them. The controls have to be properly tuned to assure that cost and other benefits are achieved.