LEDs lead the way in ongoing overhaul of campus lighting

For years, Bob Currie has been overseeing a multimillion-dollar project that, if done right, no one will notice. It's why he's always peeking up at ceilings when he enters campus hallways. 

As director of facilities services, Currie manages maintenance of Iowa State buildings, including the ongoing effort to update inefficient fluorescent light fixtures. The initiative to replace about 48,400 of the older-style T12 lights began five years ago. Even with improved and cheaper technology, the project will take six to eight more years to finish, Currie said.

When complete, the conversion could save roughly $600,000 per year in energy costs, he said.

More than 8,800 lamps have been replaced with facilities planning and management's annual $200,000 budget for upgrades, progress that seemed slow to Currie, at first. But the pace is picking up.

"Now I think we're making headway. LED technology has gotten so much better," he said.

Thinner T8 fluorescents were the go-to new lamp when the project began in 2012, the year the federal government outlawed production of new T12 bulbs. But as LEDs dropped from about $300 per fixture to $150, they've become the standard, Currie said.

"We waited until the industry caught up," he said of LEDs. "Now we can do more."

Picking fixes

Precisely how much is being done, however, is difficult to say. Though the 2012 count of 48,400 T12 lamps included all areas of campus buildings, FPM crews only overhaul the lights in public areas. Currie isn't sure how many T12s have been replaced by departments and colleges in classroom, office and building renovations. He suspects the number remaining is far less than 40,000. He estimates it'll take $5 million to $6 million to replace them all.

FPM prioritizes which buildings to tackle based on the number of T12s still in service, fixture age, accessibility, impact on building occupants and future use of the space, Currie said. One of the first to be updated was Agronomy Hall, which had more than 6,000 outdated lights. Next up this fiscal year is the 1,500 in the older parts of the Veterinary Medicine complex and Gilman Hall's 700, he said.

Some lighting in buildings is upgraded out of unplanned necessity. Existing fluorescent fixtures on the fritz aren't fixed, they're replaced with LEDs. Outdoor lights also are switched to LED as they fail, and most lighting along central campus sidewalks has been converted.

A better bulb

Made up of tiny diodes connected to an electronic circuit, LED lights offer twice as much energy efficiency gain as the newer T8 fluorescents did, a 60 percent improvement compared to 30 percent. Because they turn off and on instantly, an LED lamp with a motion detector also can keep light levels low or off when no one is around.

"We're going to have to do more occupancy sensors," Currie said.

One way the new lights will save money isn't calculated as part of the increased efficiency. Some models promise to last up to 70,000 hours before dimming, or 15 to 20 years, Currie said. That means custodians will spend less time replacing lightbulbs. T12s last 18 months or so, he said.

An unknown aspect of LED bulbs is the effect on people. There's been little long-term study of how people react to them, Currie said. But, so far, he hasn't been getting many complaints, which are common with the distracting flicker or buzz of waning fluorescents. 

"All we know is we're not having to go out and do as many repairs," Currie said.