The department owns approximately 300 staff, public and training room desktop computers. If left on all year they would consume about 280,000 kWh (~£33,000) and cause 148,000 kg CO2eq. greenhouse gas emissions. If switched off at the end of each working day the same stock would consume 60,000 kWh (£7000) and cause 32,000 kg CO2eq. greenhouse gas emissions.

The computing services department is committed to reducing the costs and greenhouse gas emissions that result from all its operations. The Director launched this effort by email in June 2009: important department instructions re. Green IT/Power Consumption.

If you have questions about this document please send an email to

1. Staff computers

1.1. Setting up

1.2. The daily routine

  • All staff are required to safely and reliably power down their desktop computer(s) and monitor(s) at the end of each working day, unless doing so would disrupt the operation of an essential service (please speak to your line manager if you are unsure).2

1.3. Before holidays and when working away from the office

  • If you have set your computer to be switched on automatically by the WOL service you should remember to disable this schedule before you go on away from the office e.g. on holiday or to a conference.
  • If you switch your computer on remotely using the WOL Service please remember to switch it off remotely afterwards.

1.4. Monitoring and reporting

2. Training rooms

Management of the objectives relating to training room computers are the responsibility of the ITLP Technical Advisory Group (ITAG) who will report to the computing services senior management group.

  • All Windows computers are switched on and off together using central management software. Computers are switched on in this way manually before the teaching starts and after the last session of the day.
  • Power Manager is used to turn all Apple computers off automatically at specific periods of the day. All monitors and computers are automatically put into sleep/standby mode after 15 and 30 minutes respectively.

3. Public access facilities

Management of the objectives relating to public access facilities are the responsibility Help Centre - ICT Support Team Liaison Group who will report to the computing services senior management group.

  • Windows computers are configured to shut down if they have been idle for 120 minutes
  • Windows computers are not switched on automatically, only when required by a user

4. Life-cycle considerations

Management of the objectives relating to the procurement, re-use, recycling, and disposal of desktop computers is the responsibility of the ICT Support and Buildings teams who will report to the computing services senior management group.


  • To be confirmed.



  • Where the option is available IT equipment will be recycled directly with the manufacturer (vendors often offers 'cash-back' and ensure the computers disks are wiped).
This allows us to copy over the MAC addresses to the PMM facility and so distinguish office computers from other devices on the network e.g. printers, switches, servers etc. We do not use the PMM facility to monitor power management on specific computers!
Apple computers cannot be switched on remotely if they are switched off but can be if they are in standby/sleep mode. Therefore, to allow HFS to switch Apple computers on just before a backup is performed Apple users must leave their computer on standby mode after work on a Wednesday. Apple users can also use Power Manager, if interested please contact James Partridge. We will experiment with OS X v10.6 Wake on Demand features to see if Apple users can rely on automatic sleep at all times e.g. avoid needing to turn their computer off at all. If successful this will be by far the most power efficient approach.