Desktop computers are often left on all the time. The main reasons for this practice are:

• An external service needs access the computer e.g. backup
• An individual needs to access their computer e.g. to retrieve a file while at a conference
• An individual wants to avoid waiting for a computer to start up

As a result computers are often on, consuming electricity without doing any useful work. Unfortunately moving computers into low power states is more difficult than switching off a light bulb - something that most people are accustomed to. This section of the low carbon ICT wiki aims to provide information about tools that can be deployed to support organisations in reducing the costs and carbon footprint of their desktop computing infrastructure.TableOfContents([2])

Tools and techniques

Automatic power management

Most desktop computers can be configured to move into low power states after a defined period of inactivity. Most operating systems can move a computer in S3 (often called "sleep" or "standby" ) or S4 ("hibernate"). Unfortunately computers may move into low power state when a process is running

1. Once in a low power state computers may not respond to being turned on remotely
2. Automatically putting a computer into S3, S4 or S5 power states
3. Issues
   • when in standby computers cannot easily be switched off automatically
   • computers don't wake from S3 or S4 reliably
   • don't want to interrupt services that may be running in background
4. Enable end-users to configure power management
5. Distribute power management setting centrally

Remote power management

Switching computers on remotely

Wake-on-LAN

• Introductory text
• ["lcict:wol"]

VPro

• http://www.intel.com/technology/vpro/index.htm

Switching computers off remotely

1. How to turn computer off remotely

Support

More efficient working practices

create matrix of: (1) practice/ activity description (2) measure of how much energy will be saved (3) who the practice is relevant to * switching monitor off will prevent it turning on when accessing computer remotely

• implement power management