Astonished at PC electricity usage

DJ_Mike

I bought one of those watt-meters a while back that monitors power consumption through a plug socket. It's been reasonably accurate in informing me about appliances that use 0-1W when idle, and also telling me that my subwoofer on my home cinema uses 16W even in its supposedly "power-saving idle" mode. However, the one thing I'd yet to plug it into is my PC. So I did this last night...

Yikes, I really wish I'd read up about/tested this before now! 200W for the PC itself when idle at the desktop... add on another 50W if I start up a 3D game. The two monitors I have collectively use 100W when switched on as well (but, to their credit, when they go into power saving mode they use next to nothing).

I'm ashamed to say I'm one for leaving my PC on a LOT, mainly because I use it to serve music to my laptop downstairs when I have guests over, or if I just want to chill in the living room. But the simple fact is, 200W x 24 hours x 365 days a year = 1,752 kWh!!! Even on my new nPower tariff, that's £156 a year, or £13 a month, if I keep my PC on 24/7 as I used to.

Needless to say I've immediately decided to make sure that PC stays off when I don't need it. I'm going to test it in Sleep mode (my preferred method of powering down) - I've read that some PCs can sleep with a minimal 1-6W of power draw, while others still use 70-150W. I'm hoping mine isn't the latter, because I really do prefer the minimal wake-up time!

So I wondered - who else has experience with PCs and their excessive energy usage? I half wonder if I should just use my laptop more permanently!

Gazpablo

I have found that some PC manufacturers are now providing electricity consumption information for their PCs in the different modes of "idle" and "active". This is very helpful. A typical PC may consume between 180 and 250w in active mode plus the monitor consumption. We are seeing now all in one PCs and net books with an active consumption of around 40w but if you have a high spec gaming computer (latest video cards etc) then you could easily be consuming 300w or more.

DJ_Mike

My PC is self-build that I put together about... 2-3 years ago? It was right as the Core 2 Duo came out so I got one of those which runs at far less energy than the competing processors of the time... still somewhere around 65W of energy draw for that.

However I bought a new graphics card recently which is sure to be the source of much of the 200W draw in my machine, although how much I can't be certain until I go chasing specs online.

Premier_2

DJ_Mike wrote: »

... I've read that some PCs can sleep with a minimal 1-6W of power draw, while others still use 70-150W. ...

When I bought one of those meters, I found my pc used about 50W even when turned off! :eek:
That could be over 1 kWh of wasted electricity per day some times.


That isn't in standby, but what appears to be off ... but still plugged in.
That was made up of 22W base unit, 18W monitor and 10W speakers (although the speakers were usually only plugged in when I needed them anyway).

Now the pc is disconnected from the mains when not in use.

DJ_Mike

I did at least confirm that my whole PC rig only uses 16W when the PC/monitors are switched off. That's likely to be coming from the internet modem and wireless router - quite acceptable considering they're providing a connection for other internet-accessing equipment in the house.

I think whether the PC has a high standby power draw or not depends on the power supply - I deliberately bought a Seasonic when I built my current PC, which not only is extremely efficient (>80% according to Silent PC Review's tests) but seems to actually switch off properly when not in use!