Campus & Community / Magazine Feature

Campus energy sleuths shed light on saving power

Allan Wilson doesn’t look like Sam Spade and he doesn’t talk like Sam Spade. And he couldn’t figure out who killed Miles Archer without an annotated copy of The Maltese Falcon on his desk in DU’s Ritchie Center.

But when it comes to sleuthing out clever ways to save electricity in a giant building, Wilson is every bit the detective Spade is. Maybe better.

Spade, the hero of Dashiell Hammett’s famous novel, unraveled the riddle of the black bird. Wilson unraveled the lighting systems in Hamilton gym, Gates Fieldhouse and Joy Burns Arena and saved the University more than $121,000 a year in power costs.

He and his colleagues also spearheaded a way of denting power costs at Ritchie by replacing the base beneath the Joy Burns ice arena with concrete, which takes less power to freeze. And they refitted the arena’s lights with energy-efficient bulbs.

Now he’s working on a way to rig Magness Arena so the high-wattage bulbs that light up hockey and basketball games won’t have to remain lit while crews clean the arena or convert the arena to other uses. It’s just another nifty way to chip away at power costs and pump less carbon into the air.

Officially, Wilson is director of building services. But the title belies his true role as one of a group of campus engineering sleuths who poke through DU basements for clues to making the buildings cost less to run.

It isn’t easy.

The Ritchie Center, for example, is a 440,000-square-foot showcase of recreation and sports that is DU’s third-biggest energy gobbler. The building is big and meant to be active, and because it’s both of those, keeping it humming isn’t cheap, costing somewhere around $1.1 million a year.

“You’ve got two sheets of ice and 750,000 gallons of water heated to 81 degrees in the pool,” Wilson says. “Everything we do is just trying to reduce the consumption already programmed into the building.”

So every bit of energy savings counts. Take Hamilton Gymnasium, for example. Until the lighting was refitted, the facility was illuminated by 116 individual 1,000-watt metal halides bouncing light off the ceiling about 20 hours a day.

The hot lights blazed even when the gym wasn’t in use, in part because halide lights take about 30 minutes to cool down before they can be turned back on.

“There’s a tendency not to want to turn them off and then back on again because the lights have to warm up,” explains DU’s new energy engineer Tom McGee. Which is expensive. So, Wilson and McGee figured out how to get the same illumination from fixtures that held high-efficiency T5 fluorescent lights. The fluorescents had plenty of light for athletics, took less power to run, were bright enough for TV broadcasts, and turned on and off with a flick.

Then Wilson and company went further, setting the lights at half-strength for all uses except games and installing infrared motion detectors. If there isn’t any activity on one of the courts for 10 minutes, the lights on that court turn off. Walk onto the court and the lights return. No power-up required.

“We halved [energy use] on the initial install,” Wilson says, “then we halved it again because we’re running only half-light most of the time.”

But there was another source of savings as well—mechanical efficiency. The old halide bulbs generated a lot of heat. When the bulbs went away, the heat went with them, meaning the building’s huge cooling system doesn’t have to work as hard.

“The mechanical load is where all the money’s spent in the building,” Wilson points out. Less load, more savings.

Sometimes, it works in reverse. Completion of DU’s new soccer stadium, conditioning complex and art annex will add to the mechanical load, Wilson and McGee concede. Lighting the soccer field for night games is like illuminating an office building, Wilson says. And the art annex has a good amount of interior air space that will need to be heated and cooled.

Which keeps Wilson at the drawing board, seeking out new ways to conserve power. Cutting back temperatures at night or zoning areas of buildings might work, he suggests. Or maybe a geothermal system, which pumps heat from the earth into buildings in winter and heat from the buildings into the ground in summer.

“Geothermal has some merit,” he says, “but it takes a lot of space.”
Solar is hot right now, he adds, but it won’t catch on until the systems can provide enough benefit to justify their cost, especially for tax-exempt entities like DU.

Then there’s wind. Last summer, DU teamed with its students to purchase 15 million kilowatt hours of wind power through a program of the Environmental Protection Agency. The bold purchase is 30 percent of the university’s annual electricity use and equivalent to the amount of power consumed by about 1,500 homes.

Even better, the wind power savings offsets 1,900 tons a year of carbon dioxide that would have gone into the atmosphere had the purchase not been made. Carbon dioxide emissions were classified a threat to human health by the Environmental Protection Agency in April.

Wind is nifty, McGee says, but fickle. It doesn’t blow when you need it to and “you can’t store it and use it later,” he says.

Which leaves the energy detectives quietly hunting for ways to save watts by asking a lot of questions? Magness Arena and El Pomar pool are the next targets.

“The answer for our campus,” Wilson points out, “is to do a little bit of a lot of things.”

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