Digital Equipment Corporation Warehouse
Andover, Massachusetts

A Quick Retrofit, A Quick Payback

In a study by an independent engineering firm, Digital Equipment Corporation learned that while H.I.D. warehouse lights were on at full power 24 hours a day, individual aisles were unoccupied about 85% of the time. Further, the study forecasted that installing new H.I.D. light control fixtures would provide a payback of the initial investment in 4.1 years, but if the existing fixtures were retrofitted with controls, payback would only take 2.9 years. Digital decided to work with the management of Controlled Lighting on a retrofit solution customized to their needs.

The lights in each aisle were retrofitted with controls and linked together to operate as a zone with motion detection. Today, rather than providing 460 watts per hour of energy, the H.I.D. 400-watt High Pressure Sodium fixtures consume only 180 watts most of the time—a solution that works with what they have, for the savings they want.