* Climate Savers tips on computing
* Purdue CIO Gerry McCartney speaking on green computing
* Purdue Condor site
* Purdue's Condor use

September 17, 2008

Sleeping computers and peripherals waste energy, Purdue CIO says

WEST LAFAYETTE, Ind. - Even when your computer appears to be off, it may still be wasting energy.

If a computer really is turned off, and other devices - such as printers or disk drives - are left on in standby mode, the system is still eating electricity.

Users can save energy, and money, by simply using an electrical power strip, says Gerry McCartney, vice president for information technology and chief information officer at Purdue University.

"When a computer is at rest, or asleep, it actually draws as much energy as a 60-watt light bulb," McCartney says. "Even if it is turned off, other devices connected to it, such as printers, monitors, hubs and other devices, draw four to five watts per hour as they stand by."

An easy solution, says McCartney, is to purchase a power strip that can be switched off when the computer won't be used for awhile, such as at night.

According to the Climate Savers Computing Web site, managing the power used by computers and connected devices can save $60 per year and prevent a ton of carbon dioxide from being released into the atmosphere.

"This may not seem like a big thing, but if you are a business with 1,000 computers, the cost savings can be noticeable," McCartney says. "And although the green effects aren't seen as easily, you can feel good knowing that you have done something tangible to help the environment."

McCartney suggests these computing power management steps:

* Use power strips that can be switched off at the end of the day. (If you work in an office that sends overnight updates or has a distributed computing system, use a separate power strip for the CPU so it can be left on.)

* Set the monitor or display and disk drives to sleep after 15 minutes.

* Set the system to hibernate after 30 minutes.

* Turn your computer off before you leave for weekends, holidays or vacations.

Purdue is doing more than just turning computers off to save energy, however. When computers are on, even if the owner isn't using them for just a few minutes, other work is sent to them. This makes more efficient use of the university's existing computer resources and reduces the total number of computers connected to the electrical grid.

Purdue does this by using Condor, which is open-source software available from the University of Wisconsin. Purdue has 20,000 computers connected to Condor - more than any other institution in the world, McCartney says.

In the coming weeks Purdue will make software available to all of its employees using Windows PCs that will allow them to connect their computer to the Condor system.

"At Purdue, if you aren't using your computer, it should either be running research jobs or be turned off," McCartney says. "We have an estimated 35,000 computers on campus, and we can have a real effect on both costs and our environmental impact if users would spend a few moments thinking about how they use those machines."

Writer: Steve Tally, (765) 494-9809,

Source: Gerry McCartney, (765) 496-2270,

Purdue News Service: (765) 494-2096;

Note to Journalists: A video of Gerry McCartney talking about green computing is available from Steve Tally, (765) 494-9809, A YouTube version of the video can be seen at

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