by Jack Curley, Products Editor
When NASA began renovations for its 600,000-square-foot, 10-story headquarters building in southwest Washington, D.C., it had a plan in place — known as the “green plan” — which stipulated strategies to maximize the potential for energy savings, water efficiency, CO2 emissions reduction, improved indoor environmental quality and resource stewardship.
A primary objective was to achieve LEED Silver certification, and doing so required securing energy efficiencies wherever possible. The new lighting system would be critical to this initiative.
Fluorescent T8 fixtures had previously been used in the headquarters building, and the property owner and manager, Piedmont Office Realty Trust, was considering replacing them with more efficient T5 2×2 fixtures.
In a parallel effort, Able Engineering’s Senior Chief Engineer supporting NASA, Tony Roberts, had investigated what Cree could bring to the table. He had placed a sample Cree fixture in another NASA facility, and NASA was impressed with the results.
“We originally considered replacing the existing T8 fluorescent tubes with T5 fluorescents, but after testing Cree’s CR22™ LED troffer, we knew it was the best solution for this installation,” said Roberts. “No other manufacturer offered the combination of performance, pricing and efficacy we desired. We continue to be impressed by the improved lighting quality and significant savings the CR22 troffers provide.”
In comparing the Cree® CR22 LED troffer with the T5, Piedmont Office Realty Trust determined that the CR22 luminaire would not only provide a better quality of lighting but also help achieve the desired energy and cost savings — with almost no toxic mercury in the fixtures. One concern with keeping a fluorescent lighting system was the increasing cost of fluorescent tubes. “Fluorescents have gone up probably 50 percent in the past eight to 10 months,” Roberts says, “and that figures to just get worse rather than better.”
Cree was the clear choice.
Each of the fixtures is also equipped with embedded Lutron dimming technology and the system is controlled by a Lutron Quantum® lighting control system. Cree worked closely with Lutron® to fine-tune timing and programming, enabling maximum control and flexibility as the building needs change.
Renovations are now complete on three floors of the building; the entire project will cover all 10 floors, some 600,000 square feet, with completion expected in the summer of 2014. The Cree CR22 troffers, some 6,500 fixtures, will be installed in total.
Roberts says the reviews of the new lighting system are very positive. “Since we got the levels adjusted the way we wanted them,” he says, “what I continuously hear is that it’s a nice even light throughout.”
On the recently completed ninth floor, the lights outside the elevators are set to 20 percent of maximum output. Those down the corridors are at 30 percent, while the lights adjacent to them are at 50 percent. But, says Roberts, “You can’t physically see the difference. You can put a light meter underneath and then see the difference, but you can’t see it with the naked eye.” …