Companies reuse data center waste heat to improve energy efficiency

Two companies have found ways to save on energy costs by reuse data center waste heat. Quebecor now heats adjoining rooms; IBM Switzerland, a swimming pool.

It seemed silly to Timothy Happychuk, the regional director for Canadian media company Quebecor. There the company was in Winnipeg, Canada, where the average low temperature in January is minus 10 degrees Fahrenheit. And yet it spent money to mechanically cool its data center, and then more money to heat the rest of the building.

"While it was 35 below [Celsius] outside, I would be paying a tremendous amount of money to cool the data center while I was paying to heat the rooms around it," he said. So he did research on ways to recover waste heat.

For more on data center energy efficiency:
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Reusing the waste heat from a data center may not make the server room itself more efficient, but depending on how heat is reused, it can save a company a significant sum of money. In its report to Congress last year on data center energy consumption, the federal Environmental Protection Agency suggested the practice. And the idea has gained traction.

Heat recirculation at Quebecor
Happychuk's path to reusing Quebecor's data center's waste heat wasn't easy. Many of the infrastructure vendors he explored -- Liebert, for example -- weren't "even willing to talk about it." So Happychuk did the research himself.

At Quebecor, the 2,500-square-foot data center sits on the ground floor, while the editorial offices of the Winnipeg Sun sit directly above it. Adjacent to the data center is a large warehouse that includes the newspaper's printing presses and loading bays for trucks to pick up and deliver loads.

Happychuk oversaw the installation of air-side economizers that draw in outside air. The economizers include baffles that open to varying degrees depending on the outside temperature and how much cooling the data center needs, as well as a series of three filters that pull bacteria-sized particulates out of the air and a humidifier to condition it for the IT equipment.

After the air cycles through the approximately 100 eight-way Intel Xeon-based servers, it warms up in the process. It then goes into an overhead plenum, where about 10% of the air is re-circulated to warm the outside air that comes into the data center.

Happychuk ran another duct out of the exhaust plenum to the intake duct of the editorial office upstairs. Quebecor also added a second thermostat to its editorial offices; the first controls the traditional heating furnaces.

"They're getting the ultimate: nice, warm humidified air for free, compliments of the huge server racks below them," he said. "There's nothing worse than a bunch of unhappy writers."

That used up another 60% of the waste heat. The data center dumps the remaining 30% into the adjacent warehouse, which can get cold quickly with the poor insulation and loading bays, which open and close constantly.

All of these processes are controlled by pneumatic baffles that open and close depending on readings off thermometers within the ducts. In the warmer months of the year – which are few in Winnipeg – hot air from the data center that isn't reused gets sent outside.

"We were concerned we wouldn't have enough excess heat capacity," Happychuk said. "But we were actually running out of places to apply it."

Happychuk is now in the process of estimating how much money the system has saved Quebecor. But regardless of the dollar savings, the maintenance manager has encouraged Happychuk to keep up the good work. Heating costs in the editorial offices are now zero and drastically reduced in the warehouse as well.

"I just happen to be really cheap and hate wasting stuff," he said.

Using data center heat to warm a swimming pool
Meanwhile, in Switzerland, IBM helped a company build a colocated data center in a former military bunker and designed it so that the waste heat is piped away to warm a nearby municipal swimming pool.

The 2,300-square-foot data center, run by GIB-Services, is located in Uitikon, Switzerland, and sits about 25 feet below the earth, as well as about 500 yards away from the swimming pool. The data center is already built, while the heating component should be running by the end of August.

According to IBM Switzerland Site and Facilities Manager Jeorg Schanze, the company's data center has capacity for about 200 servers and has custom-made overhead cooling units on the ceiling. The hot exhaust air will warm water in a heat exchanger, which will then be piped to the local swimming pool and used in a heat exchanger to warm the pool water. Previously, the town warmed the water using heating oil.

Let us know what you think about the story; email Mark Fontecchio, News Writer. You can also check out our Server Specs blog.

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