Guidelines for Energy Conservation and Computing Equipment

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Introduction Turn these off Computers Screen savers and power-saving modes Purchasing decisions Common questions References	See the References section at the bottom of this page for links to more information on other pages.

Title: Guidelines for Energy Conservation and Computing Equipment
Status: Final
Author: Security Office and Alliance of IT Service Providers
Audience: All UIUC faculty and staff
Effective Date: 4/1/2007
Next Review Date: 4/1/2008

Introduction

The following guidelines were created in response to a call from Chancellor Herman to the campus community to find ways to reduce energy consumption on campus. In particular, computers and supporting peripherals were singled out by Chancellor Herman for attention; computing equipment draws approximately one-third of the electricity used in a typical office.

Generally speaking, all computing equipment should be turned off or placed in some sort of "power saver" mode when not in use. However, during off-hours many computers perform backups or update and patch software (such as antivirus definitions) and the operating system, and it is therefore important to configure energy-saving features so as to not interfere with these critical update processes.

We strongly encourage you to read through these guidelines and to contact your departmental or college IT Professional support staff with questions or for assistance. Those desiring additional information beyond that covered here will find a references section at the bottom of this document.

Turn these off

The following equipment should be turned off (or, if possible, put in Sleep Mode) at the end of the day and over weekends.

• Monitors
• Printers
• Scanners
• Powered speakers

Please note that many modern devices, monitors in particular, continue to draw 9-16 watts of power even when turned off. To eliminate this draw, use a power strip that has the ability to switch off certain outlets and not others (or, alternatively, use two separate power strips) so that you can turn off any of the above without turning off devices that need to remain powered, such as your computer's CPU.

Computers

Please contact the IT Professionals that support your computer to discuss whether or not to turn your computer off at night. Otherwise, you may unintentionally disrupt backups and system updates, leaving you at risk of data loss or a computer virus or attack.

As a general rule, turn your computer off at night (or, if possible, put it in Sleep Mode) when you are not planning to use it. Although many computers back up data and update software and the operating system at night, most will attempt to update their security software upon startup. For example, the antivirus software licensed by the campus will attempt to update itself upon computer startup (on Windows) regardless of when it has been told to look for updates.

To ensure that your computer is always up to date, you should periodically force a manual update of the operating system and your antivirus software. Before proceeding, contact the IT Professionals that support your computer. Additional information on securing your computer can be found in the folloing locations:

• for Windows computers: http://www.cites.uiuc.edu/security/by_os/index.html
• for Apple computers: http://www.cites.uiuc.edu/security/by_os/macosx.html
• for Windows antivirus software: http://www.cites.uiuc.edu/security/antivirus/winav8.html
• for Apple antivirus software: http://www.cites.uiuc.edu/security/antivirus/macav.html

Screen savers and power-saving modes

Screen savers do not reduce the use of power by your computer; once your screen saver kicks in, your monitor will draw its full power load. All users, whether on desktops or laptops, should configure their computers to use the power-saving or energy star modes that shut down power to the monitor, hard drive, and computer itself after periods of inactivity. Putting your computer in sleep mode allows it to use substantially less power, allows it to respond to some types of network activity, and allows you to not power off the computer.

For a number of years the common Windows and Apple operating systems have supported these power-saving modes.

Windows
Select the Start Menu -> Settings -> Control Panel -> Power Options. This should bring up a Power Options Properties dialog box that allows you to set the time to elapse until separate components power down. This is the same dialog box that can be accessed through the Display Control Panel under the screen saver tab.

Information from Microsoft: Power Management in Windows XP

Apple
Select the Apple Menu -> System Preferences -> Energy Saver. This will bring up a dialog box for setting sleep times for the entire system, the monitor, and the hard disk.

Information from Apple: Mac OS X: About Energy Saver Options

The following are the industry-standard recommendations on how long a system component can be idle before it should be powered down.

Component	Time Period
Monitor	20 minutes
Hard disk	30 minutes
System standby or hibernation	90 minutes

Please note that you may want to tweak these settings depending on your system and usage habits. For example, many laptop users choose much shorter time periods when running on battery so as to extend the time between charges.

Purchasing decisions

• Although the initial purchase costs of laptops may be higher, they draw significantly smaller amounts of power in operation than desktop systems. These savings can be as high as 80-90% and should be factored into the purchasing decision.
• Networked printers can also serve entire workgroups and may also result in energy savings over individual printers.
• LCD monitors offer up to 60% power savings over CRTs and produce less heat.

Those wishing to calculate the true costs associated with computing equipment may want to spend some time with the Excel-based calculator created by Columbia University at

http://www.environment.columbia.edu/excel-files/Columbia_Computer_Energy_Usage_Calculator.xls

Please note that the energy star tags found on computers are not a reliable guide to energy efficiency. They refer to the computer's support for power-saving modes (see above) and do not reflect the actual power usage of the system.

Common questions

Won't turning my computer on and off every day damage it or decrease its usable lifetime?

No. However, if you are worried about this, use the power-saving features of your system to achieve almost the same power savings without having to physically turn the computer off.

When my computer goes to sleep, will I lose my network connection?

You will probably lose your connection to the campus VPN and QuickConnect.

Can I use Windows Remote Desktop from home if my computer is in power-saving mode?

Remote Desktop will work if your monitor is turned off. Talk to the IT Professionals supporting your computer about using Remote Desktop in conjunction with power-saving modes.

My office uses a group printer. Should I turn that off at night, too?

This should be a group decision based on considerations such as how often someone from the group may need to print at night, how long the printer takes to become ready to print, and how close the printer is to group members' offices.

References

Resource	Link
Nov 8 2006 Message from Chancellor Herman (use NetID and NetID password to access)	MASSMAIL - Reducing Energy Costs on the Urbana Campus
To find out who your network administrator is	OpCenter NetAdmin Locator
Comprehensive information from the University of Colorado	Green Computing Guide
Information from Apple	Mac OS X: About Energy Saver Options
Information from Microsoft	Power Management in Windows XP
University of California at Santa Cruz Guidelines	Campus Conservation Guidelines - To Keep The Lights On
US Government's Energy Star recommendations	Office Equipment
Information from energy-solution.com	More About Enabling Sleep Mode and EZ Save

Technical professionals may wish to familiarize themselves with the various approaches to "wake on LAN." A useful starting point is the Wikipedia article, which collects a number of good references.

http://en.wikipedia.org/wiki/Wake-on-LAN