Save £100 by greening your PC's power bill

4. Sort your monitor power settings, ditch the screensaver
Money saved: £25 a year
With their sizes on the increase, monitors are drawing an increasing amount of power. An average 20 inch widescreen one such as the Philips 200XW7EB uses 48 watts -- the same as four energy-saving bulbs -- when switched on. But its power consumption drops to a tiny 1 watt on standby.

If you left this Philips monitor on all year round, you'd burn £50.37. But if it was automatically dropping into standby for 12 hours every day, you'd cut that figure in half in a stroke.

You can tweak your monitor's power settings using your computer. In Windows, you'll find the option in Control Panel, under Power Options -- just set the time on the 'Turn off Monitor' option. On a Mac, you'll find the option under Energy Saver in System Preferences. Mac heads could also try Sleep Display 2.1 or LightMe.