Beyond The 'Glass Room'

The traditional approach to data-center cooling, going back to the days of mainframe "glass rooms," has been to provide good ventilation and a powerful central air conditioning unit. But the trend toward packing more computing power into each I.T. device and more devices into each rack means it's not always enough to rely on the circulation of chilled air through the room. Gartner recently predicted that by 2011, the predominant strategy for high-density computing will be to use cooling equipment that's built into each row of server racks or installed in the racks themselves.

So, where the old Cimarex computer room relied on an 10-ton Liebert air conditioner, the new one wound up being built around American Power Conversion's InfraStruXure product, a server rack system that features integrated in-row cooling, along with APC's battery backup technology. Cimarex also chose to take advantage of APC's Hot Aisle Containment system—an arrangement where two back-to-back rows of server racks vent their exhaust into an enclosed area with a roof and doors on either end. This keeps the hot air out of circulation until it can be cooled and vented out the front of the server rack.

"Rather than cool the whole room, we trap the heat into this area and only remove the heat from that section of the room," McPhearson explains.

Best known for its power protection technology, APC has spent the past several years positioning itself as a vendor that can also help data centers address their cooling and energy efficiency issues. The West Kingston, R.I., company was acquired in February by Schneider Electric, a global power equipment manufacturer based in Paris, and merged with Schneider's power protection subsidiary, MGE. At a media briefing in June, APC chief technology officer Neil Rasmussen said the firm will continue to focus on improved cooling as one of the best ways to enhance data-center energy efficiency and reliability.

In-row cooling can be more efficient because the cool air can be delivered closer to the equipment to be protected, Rasmussen says. In the traditional approach of cooling the whole room, the air coming out of the air conditioning vents needs to be made that much cooler because it's not being delivered with the same precision. "So, you end up with 45-degree air coming out to the floor," he says, even though most I.T. equipment doesn't need to be kept anywhere near that cool. "And it's a lot more expensive to make 45-degree air than 70-degree air." Also, while APC's power protection equipment is rated about 97% energy efficient, making further gains hard to come by, the company believes there's potential to improve the efficiency of data-center cooling by another 20% to 30%, Rasmussen says.