What is the cost of running a computer PC or leaving it on all the time?

weegie.geek

slewis1972 wrote: »

The thing is, a pc consumes more power when it starts up, so I personally would be interested to know if both amounts are close or way out.

Does it though? I mean I'm sure it technically does, but it takes less than a minute to boot from cold and a matter of seconds to recover from hibernation. You'd have to turn the PC on and off a lot for it to make a noticeable difference.

I'd take up the slewis challenge, but week 1 is my normal pattern pretty much.

I'm building a raid set just now, but I'll restart the pc after and measure usage when booting up to see how much more power it guzzles when booting.

philoio

It depends heavily on your PC, what it is doing, and what power saving features it has. I do not fancy going into this so i will assume 125w suggested earlier. (it seems a reasonable estimate). I will also assume 10p per kwh.

This gives me the following.

30 days x 24 hours in a day = 720 hours in a month
720 hours x 0.125Kw = 90kWh used in that month
90kWh x 10p = 900p = £9 per month

So how much of that could be saved by turning it off when you are not using it? For me i would expect to be looking at £100 per year... dam perhaps i will turn it off tonight.

[Deleted User]

weegie.geek wrote: »

Does it though? I mean I'm sure it technically does, but it takes less than a minute to boot from cold and a matter of seconds to recover from hibernation. You'd have to turn the PC on and off a lot for it to make a noticeable difference.

I'd take up the slewis challenge, but week 1 is my normal pattern pretty much.

I'm building a raid set just now, but I'll restart the pc after and measure usage when booting up to see how much more power it guzzles when booting.

Last time I checked, my media centre PC used a peak ~250W in the minute(?) or so from cold boot to the Vista login screen.

Mostly I just leave it in S3 mode (hibernate) when I'm not using it, though. The usage is in the realms of 1-2W (IIRC), which is negligible, and it wakes up almost instantaneously.

mardatha

thanks Philoio, I cant do the technical stuff, that gives me a figure and is easier. Maybe better start using the ancient laptop instead...

Cardew

If you want it stated in purely cost terms.

Most desktop PCs will use between 1.5p to 2.0p per hour when running.

However you should have the power management set so that it hibernates after xx minutes not being used. Then it will use very little indeed - all day for a penny or so.

Most laptops will run for 3 to 4 hours for 1p and as above much less when they hibernate.

mardatha

wow, that's a big difference, thank you !

Pssst

Surely the only means by which you could measure consumption in various states i.e working/standby mode would be to use an ammeter measuring the AC current being consumed? This would necessitate some knowledge of live electrical testing and a good quality meter.

Phlik

Use one of these fellas, monitors your usage down to 0.01w

http://www.maplin.co.uk/Module.aspx?ModuleNo=223573&C=Maplin&U=SearchTop&T=power%20meter&doy=11m7

Phlik

storminbalder

You should also factor in the wear and tear costs involved in constantly turning on and off you computer.

It is a given fact, the there is a tiny additional chance of any electronic component failing when doing so.

Cardew

Huw_Sharpe wrote: »

My PC uses 242watts when idle, and about 375watts when doing something processor intensive. Add another 100watts per 28" screen.

.

What sort of computer?

That is huge consumption and certainly not representative of most PCs. 150w to 200w is the figure for most powerful home PCs.

By 'idle' you mean hibernating or sleeping?