Sustainable Design  

The Big Switch

A school, a hotel and an ice-skating rink epitomize the visual quality and energy-saving benefits that result from relighting
BY PAUL TARRICONE

Although new construction continues to sputter along, there is plenty of existing space that’s ripe for relighting. How much is anyone’s guess, but suffice it to say, it’s a pretty big number— one with lots of zeros at the end. In fact, data from the U.S. Department of Energy suggests that about 2.5 million commercial buildings (half the nation’s inventory) are candidates for energysaving lighting upgrades. Here are three—two in the U.S. and one in Canada—that took the hint.

Rockford High School

Rockford High School in Michigan was the Goldilocks of lighting. In the classrooms, the lighting level was too high. In the gymnasium, the lighting level was too low. Today, the lighting levels are just right—as are the energy savings.
The $400,000 lighting renovation encompassed more than 130,000 sq ft of space, including several other gymnasiums in the district. The high school, however, represented the majority of the project— even though it’s only 17 years old. “It is not common to find buildings built in 1993 that have T12 lamps installed,” says lighting designer Amy Zeboor of WPF Engineering, Belmont, MI, in reference to the classroom lighting.
What Zeboor and colleague Lynn Surdock discovered was that the T12 fixtures resulted in extremely overlighted classrooms (94 footcandles) and poorly illuminated vertical teaching surfaces. Each 900-sq ft classroom had 14 or 15 of these three-lamp T12 dual-switched parabolic fixtures. “As this is the school district my children attend, I was actually outraged to see 94 fc in these spaces as well as T12 lamping,” says Zeboor. “The owner was using 34-W T12 super-saver lamps, but the project was so overlit that it did not make sense to just retrofit to T8. We did an analysis and found that it would be a two-year payback to retrofit these spaces. In 1993, T8 lamps should have been used, and at that time 50-60 fc was probably still the norm for most classroom design. Typically, nine three-lamp fixtures was the norm.”

Bypassing the T8s, WPF redesigned the classrooms with eight Cooper Metalux Accord fixtures utilizing two T5 lamps with a stepped dimming ballast. “I’m sure the owner thought I was out of my mind when I suggested we look at an alternative to T8 retrofit. I will say they were very progressive and did hear me out,” says Zeboor. The T5 solution appealed to the school district, in part, due to the position of the ballast compartment, which is accessible from below the ceiling. Energy in the classrooms was reduced 60 percent, while the footcandle level has been slashed to 35 fc on average, in line with IES recommendations. In short, the classrooms better reflect 2010 teaching techniques: With today’s extensive use of laptop computers, the lower light level is more comfortable and better suited to the task.
Controls provided the finishing touch. “We added occupancy sensors to control lighting on/off so that the lowest level of light comes on with the occupancy sensor,” says Zeboor. “We’ve found that in many cases, the lower light level is providing additional savings we were not anticipating.” Five gymnasiums (including two in the high school) were also relighted. Here, though, the problem was underlighting not overlighting. The typical light level produced by the existing 400-W metal halide fixtures was 25 fc. But Zeboor notes that “in many instances, due to the age of the metal halide lighting and poor vertical illumination, the gymnasiums appeared much worse than 25 fc. In the North Rockford Middle School, it was actually closer to 15 fc. This is the gymnasium I would sit in every Saturday while my son played basketball, and yes, the lighting made me cringe.”
WPF’s redesign called for T5HO fluorescent high-bay fixtures (Metalux F-Bay from Cooper) in a onefor- one replacement. A combination of four-lamp and six-lamp fixtures were installed in existing fixture locations to minimize interruption of the year-round gym use. The high-school gym was lighted to a Class II facility-level (approximately 80 fc for court competition and 50 fc for general light level). The other gyms were lighted to 35 fc.
WPF Engineering also showed its support of the school in another way. The company obtained Energy Policy Act tax credit for these projects and donated the money back to Rockford Public Schools. “We are now in the process of additional retrofits for gymnasiums. On top of the EPAct tax credits, which the design professional can obtain for non-profit clients, we are able to obtain utility rebates, which will go directly to the school,” says Zeboor.

Then: T12 and Metal Halide Luminaires
Now: T5 and T5HO Luminaires
The Bottom Line: Overlighted and Underlighted Spaces Remedied

Hyatt Regency Grand Cypress Resort

In what amounts to a redesign of a redesign, the Hyatt Regency Grand Cypress Resort in Orlando removed existing fluorescent, skipped right past the specified MR16s and installed LED luminaires in a sweeping hallway renovation project. The relighting project also included LED replacement uplights in the main lobby. By relighting these areas, hotel management hoped to achieve the warmth of halogen, without the wattage and maintenance requirements.
Hyatt’s remodel complies with the Florida Department of Environmental Protection’s Green Lodging program, a voluntary initiative for hotels and motels across the state to adopt cost-saving green practices to conserve energy, reduce water consumption, protect air quality and reduce waste. A total of 636 LED downlights were used in 54 hallways, and 35 LED luminaires were installed in the 10,000-sq ft lobby. The existing lighting in the hallways was comprised of two 40-W fluorescent lamps above each door. The original redesign called for a 50-W MR16 fixture to replace the fluorescent, but Tommy Mydlo of Regency Lighting, Orlando, took one look at the specification and told hotel management that with the projected 2,000-lifetime for the MR16s, “they were going to have to hire one maintenance guy just to change lights all day.”

Mydlo mocked-up two model rooms in the hotel and proposed using a recessed 12-W LED luminaire (from Cree). The project essentially went from an existing 80-W system to a proposed 50-W system to an installed 12-W system. What’s more, due to where the LED luminaires were positioned above the guestroom doors, the total number of fixtures was reduced from more than 800 to 636. More important, says Mydlo, is “getting that halogen feel of 2,700[K] and a CRI of 90. Halogen on day one, day five and day seven is going to look the same. That’s what we required of the LED.” Mydlo estimates at least a 50,000-hour lifetime at 70 percent lumen output from the LED system. The ROI for the hallway portion of the project is expected to be just nine months, with a savings (in energy, labor, cooling and lamp cost) of more than $130,000 forecast for the first year.
The lobby had halogen 90-W PAR38 fixtures in place. A one-for-one switch-out replaced these 35 fixtures with 12-W LED floor-mounted uplights from Cree. Management’s objective, says Mydlo, was to maintain “the Zen, Feng Shui feel of the lobby,” once again with a CRI of 90 and the 2,700K warmth. The luminaire also produced the tightly focused beam (20 deg) required to highlight the lobby’s palm trees and indoor garden.

Then: Fluorescent and Halogen Luminaires
Now: LED Luminaires
The Bottom Line: Proper Color Rendering and Warmth

The Bowden Ice Arena

The puck moves very fast, so it’s best to see it clearly. Officials at the Bowden Ice Arena in Alberta, Canada, swapped out 36 400-W metal halide luminaires for the same number of highbay LED luminaires (from Albeo Technologies), not only for the projected energy savings but to give hockey players and spectators a better look at the disc. Each luminaire now floods the ice with 25,000 lumens at 79 lumens per watt.
“The fast pace of hockey, the high speed of the puck, and the need for quick action demands high lighting levels,” says Andy Weiss, manager of administrative services for the Town of Bowden. Bowden framed the project as a green design initiative. “The mayor and Town Council directed administration to investigate eco-friendly lighting for the arena. LED lighting was the preferred option right from the beginning of this process,” says Weiss.

As is often the case with LEDs, the three-legged stool of energy, maintenance and quality drove the decision. “Obviously, energy savings was the number one motivation. There are no more bulbs to replace over ice, and the whiter, cleaner light color is perceived as higher quality than metal halide which fades as time progresses,” says Weiss. Even, so solid-state lighting was new terrain for Bowden. “LED lighting for arenas is new in Canada, so other than limited exposure at trade shows, none of us really knew exactly what to expect.”
The one-for-one replacement made installation “painless,” says Weiss. “Take down the old fixtures and hook the new ones up on the same chains, in essence.” With fixture mounted at 16 ft, illumination levels on the ice were increased 60 percent from 50 footcandles to 80 fc, while energy consumption was lowered 28 percent from 458 watts (including the energy draw from the ballast) to 324 watts. “The lighting levels are significantly brighter than our existing lights and personally much brighter than I had anticipated. The lighting shadows on the ice are now completely eliminated.” Finally, the instant-on and instant-off has also been a benefit. “Metal halides need time to warm up and cool down if you turn them on and off, then back on again immediately,” says Weiss.

Then: Metal Halide Luminaires
Now: LED Luminaires
The Bottom Line: Brighter Ice

May 2010