Sun Cools Down the Data Centre

“Our history hasn’t been great,” said Dean Nelson, Sun Microsystem’s global design director for data centres. “But we don’t need rules and mandates, we need best practices,” he said, welcoming the recently-launched EU Code of Conduct on Data Centre Energy Efficiency.

Nelson’s idea of best practice is probably about three years ahead of anything you’re likely to see in many data centres, though. For the last few years, he ran the team consolidating all Sun’s own servers. He saved the company millions of dollars, and in the process championed new ways to cut the cost of cooling servers.

“We decided to clean up our own back yard,” he says. “We didn’t set out to save the planet – we simply didn’t know what servers we had, where they were or how inefficient they were.”

The project cut Sun’s IT budget by millions, mostly through power savings, and reduced the size of its datacentres by up to 66 percent. It also turned Nelson into a hero of the green data centre movement.

The key was a new approach to cooling. In Sun’s Santa Clara centre it cut electrical power consumption by 75 percent, even while computing power went up four times. The achievement has drawn 3000 visitors to tour the site in the last year.

The secret had nothing to do with IT, he says: “I sit in the real estate group, because cooling is about architecture. If you build the right data centre with brutal efficiency, you get the ecological benefits.”

The first job is to size the problem, he says, using PUE (Power Usage Efficiency), a measure from the Green Grid iniative, which divides the amount of power a data centre uses, by the amount that actually reaches the computers.