The last time Laurier Nichols was in Chicago, he made sure to visit the United Center, home of the Chicago Blackhawks and Chicago Bulls.
Nichols wasn’t there to watch a game. A Canadian engineer and vice president of the Montreal firm Dessau, which designs and maintains sports venues, he wanted to see how the largest arena in the United States keeps the ice from melting.
Not particularly easily, as it turns out.
As the Stanley Cup Playoffs have skated into the humid early summer, and the NHL has expanded from cities such as Calgary, Buffalo, and Pittsburgh to warmer climes like Phoenix, Dallas, Los Angeles, and Tampa Bay, the technology required to keep the ice cold and the air dry is putting in more overtime than the Boston Bruins.
Basketball, too, has bounced into June, and into San Antonio and Miami, where huge amounts of air conditioning is required to chill the Heat. More baseball stadiums are also being enclosed, and need new engineering to ventilate and cool them.
But it’s hockey rinks that suck up the most energy, Nichols says.
“Even in Montreal, it’s quite hot outside in August” when the ice arenas open for school hockey practice, he says.
Just how complicated is the microclimate created inside hockey arenas was made clear last month in Detroit, where the 34-year-old Joe Louis Arena became so overheated during a game between the Red Wings and the Blackhawks that the ice turned to slush and fans took off their shirts as the temperature in the stands neared 86 degrees.
It evoked a Stanley Cup Playoffs game between the Bruins and the Edmonton Oilers in the old Boston Garden in 1988, which had to be suspended when a power failure killed the air conditioning, the temperature rose to 80, and players skated in circles in a futile attempt to clear the B-movie fog that descended on them.
In fact, it’s the air conditioning, and not the complicated cooling system in the ice, that sucks up most of the energy in hockey arenas—especially when there’s a large crowd of warm bodies and high-intensity television lights, as during playoff season. And while some teams have tried to reduce the environmental impact, it’s not easy.
Indoor hockey arenas are far different from the wintertime backyard ice rinks made with favorable weather and garden hoses. They’re built on foundations of concrete slabs inlaid with miles of metal pipes three inches apart through which runs brine refrigerated to about 10 degrees below zero, dropping the surface below freezing. Thin layers of water are then poured on top of it and allowed to freeze.
It’s a seemingly simple system complicated by lots of moving parts and pumps and huge 200-horsepower compressors—two each in the typical NHL arena, with a third as a backup—propelling the brine through the pipes at 1,200 gallons per minute. So much trouble did the Southern Professional Hockey League’s Augusta RiverHawks in Georgia have with the ice system in its James Brown Arena this spring, the team has shut down for at least the next season.
One way some arenas reduce their energy costs is to use the waste heat from the freezing process to warm the seating areas immediately around the ice, the management offices, and the water used in bathrooms and kitchens and the Zamboni machines, though most venues inexplicably cool the ice and separately heat the stands, Nichols says.
A minor-league arena in British Columbia where the American Hockey League’s Abbotsford Heat plays has even started using recycled rainwater to make the ice, collecting it from the building’s roof.
Steps like these do little to offset the huge power drain of air-conditioning systems that have to not only cool the air, but dry it, to prevent a fog like the one in 1988 in Boston. This takes 10 times as much energy as keeping the ice from melting.
“The load of that is quite high,” Nichols says.
Humid air in new NHL towns like Tampa Bay and Sunrise, Florida, carried indoors by the ventilation systems, has to be dried out through a desiccant system to remove the water vapor. In a 20,000-seat arena, that means moving 400,000 cubic feet of air per minute, Nichols calculates.
Vast new arenas such as the United Center in Chicago and the TD Garden in Boston, opened in 1994 and 1995, respectively, and the homes of this year’s Stanley Cup Playoffs, have sophisticated technology that can do this, with the added challenge that Chicago’s arena is the nation’s biggest and the TD Garden, at 10 stories, one of its highest.
As for Nichols, he tries to visit hockey arenas whenever he travels, partly because he’s Canadian, he says, and partly because of his vocation.
“It’s both reasons,” he says. “But I’m interested most in the engineering.”