Santa Clara, Calif.--It's not the heat and high temperatures that can damage servers and other data center equipment. It's the cooling process.
NetApp, the large-storage vendor, experiences more equipment failures when it tries to cool its data centers too rapidly than when it lets its equipment wallow in waste heat, said Dave Shroyer, a controls engineer with the company, during a meeting at the ConnectivityWeek conference taking place this week in Santa Clara.
Over the past few years, NetApp has become a de facto poster child/guinea pig for green IT and building management because of its aggressive adoption of technologies for curbing power consumption. In 2006, the company started focusing on internal energy consumption. A 2008 data center retrofit, funded by a $1.4 million rebate from PG&E, saves NetApp $1.2 million a year.
More companies will go through similar experiences. In California, demand response programs, which now have the ability to switch off lights and air conditioners to curb peak power in potential brown-out situations, will be increasingly exploited to modulate power on a daily basis, says Albert Chiu, who runs demand response program initiatives at PG&E.
"We want to use demand response and dynamic pricing to influence market pricing," Chiu said. "The low-hanging fruit [i.e., changing out inefficient light bulbs] is not there in building management."
In California, new buildings with 500,000 square feet or more of space that get half or less of their lighting needs from sunlight will have to install lighting controls and join demand response programs, Chiu said.
By 2011, approximately 650,000 commercial and industrial buildings in California will receive their power under dynamic pricing schemes. Business consumers can opt out, but dynamic pricing will be the default, Chiu said. Only high-use customers get dynamic pricing as a default now.
"Most buildings are wasting 30 percent of their energy off the bat," said Ed Richards, director of business development at Cisco, who also participated in the roundtable. Ed helped found of Richards-Zeta Building Intelligence, a building management systems company bought by Cisco about 18 months ago.
Back to the case study. Heat is not as big a problem as once envisioned in data centers, Shroyer added. Like a lot of companies, NetApp now divides up its data centers into hot/cold aisles that generally are kept at 95 degrees and 75 degrees, respectively. In the past, data center managers kept everything at a universal chilly level. The company could actually push the temperatures higher, but the employees would complain.
"Our guys like being out of the meat locker, but now they don't want to have to wear Bermuda shorts or carry around a little fan and a pitcher of water," he said.
--You really can turn down lights without employees caring. NetApp has managed to cut its lighting load at times by up to 50 percent. And if you turn the lights down gradually, taking a full hour to dim, for instance, few will even notice.
--Overall, employees like the system. Before the company started dynamically controlling temperatures, some employees complained about being cold, he said. Many also like the fact that the company is doing the so-called right thing. The overall set points for NetApp's thermostats are now 30 percent higher.
"It turns into a customer service thing" with employees as customers, Shroyer said. Chiu reported similar results at places like the retailer Kohl's and some manufacturers participating in northern California demand response programs. At Kohl's, when customers were told the lights were dim to save on peak power, the feedback was positive, Chiu said.
--Air side economizers, which let in ambient air to cool data centers, work, or at least they do in Northern California. Because the air in the region is also comparatively dry, NetApp also does not have to employ humidifiers to balance that variable for their data centers.
"There are three months in a year I can turn off the chilled water plant" for the data center air conditioner, Shroyer said. "The load, when it is on, is now 30 to 50 percent less because I am using a blend of outside air."
Microsoft employs air side economizers in its data center in Ireland.
--Throttling cooling also reducing maintenance bills and extends the life of capital equipment, NetApp has found.