Computer electricity consumption

trisha wrote: »

My computer goes on at 7:00 am until I go to bed around midnight, my monitor does go into power saving mode.

Is it using a lot of electricity keeping it on all day, rather than switching it on and off a few times a day to check my mail etc ?

TIA
Trisha

You don't say whether your PC is a laptop or a desktop, but I assume from the reference to a monitor, it must be a desktop. Is the monitor an old-type crt or a more modern lcd? A crt consumes almost double the power of an lcd (90W as opposed to 40W).

My old desktop system, with 17in crt screen, used to consume 180W when idling. That's 1 unit of electricity (1 kWh) for every 5.5 hours of use.

My new Core Duo desktop, with 19in lcd screen, consumes 125W idling but this can quickly rise to around 160W when the processor is heavily loaded.

If you only use the computer occasionally during the day, it will obviously save you a fair amount of money if you switch it off after each use.

Also, always switch it off completely i.e. pull the mains plug or switch off at the socket. All computer systems continue to draw a small amount of power, even when apparently closed down (around 10W). Wall-warts, which provide power for ancilliary equipment such as scanners and speaker systems can also continue to draw power if left plugged in to a live socket. That's why it's not advisable to leave mobile phone chargers plugged in permanently.

There can be many items around the house permanently consuming small amounts of electricity, so it's very instructive to measure these using a power measuring device as suggested by Cardew. I bought one from Maplins and was amazed at the numerous 5 watts here, 7 watts there, that all add up to a considerable cost when added up over a year.

Geoff