Diamondbacks prove to be experts at keeping heat at bay
PHOENIX — At first blush, the thought of putting baseball’s All-Star Game in Phoenix was as risky as a Super Bowl in Green Bay, and the Arizona Diamondbacks needed a lengthy lobbying campaign to land it.
It’s hot. It’s the monsoon season, when the humidity rises to about 30%. But both at Chase Field and in downtown Phoenix this week, the tripledigit temperatures seem manageable, thanks to technology and an assist from organizers.
“The biggest concern was the heat, and we had to assure everybody that we do it every year and that everybody’s fine,” said Derrick Hall, Diamondbacks president. “Having the luxury of having a retractable roof, a nice cooling system and making sure we kept all the festivities within close proximity, we knew we’d be fine.”
Chase Field, which opened in 1998, was the first retractable-roof stadium with a natural-grass playing surface, which means the roof must be open regularly for sun. Typically, it is opened every morning at sunrise and closed about three hours before game-time to cool the park to about 78 degrees.
This week, however, the roof has remained closed since Sunday morning to accommodate rehearsals and other All-Star activities. And that made cooling it for Tuesday night’s game easier.
“Normally we don’t have the roof closed for two or three days. We’d love to keep it closed and keep the airconditioning running,” said Jim White, Diamondbacks director of engineering, who doesn’t have to worry about the grass or paying the electric bill.
The 8,000-ton cooling system — the equivalent of cooling 2,500 homes of 2,000 square feet — uses chilled water and is part of the system that serves more than 30 downtown buildings. The plant, a separate building, is just outside the ballpark.
Tuesday night, White expected the temperature on the field to be 72-74 degrees, about 4 degrees cooler than normal. (The temperature inside at first pitch was, in fact, 72 degrees compared with 99 outside). When the roof is open in the morning, he said, the steel and concrete “act as sponges” for the heat, and ballpark temperatures can’t be reduced that much in three to four hours.
Opening and closing the roof takes 4½ minutes and costs $2-$3. It is done with two 200-horsepower motors triggered from the engineer’s control room in left-center field of the upper deck. It was last opened for a game June 17.
“The coldest I’ve been in Phoenix in August is at Chase Field,” said Scott Dunn, associate director of communications for the Greater Phoenix Convention & Visitors Bureau, adding the crowd was sparse that night. “I sat there and shivered.”
Organizers caught a break this week — the highs of 100-101 degrees are about 7 degrees below normal. And they also dodged the freak dust storm that blanketed the city with dirt just a week before game night.
“Major League Baseball panicked. They called us and said, ‘What is that thing?’ ” said Hall, who assured the commissioner’s office it was a fluke. “I’d never even heard the term ‘haboob.’ I did panic because I knew we’d have to do a major cleaning all around the property.”
Fortunately, he added, the club was able to close the roof before the storm hit downtown.