Can a switched on empty mains socket use power?

In Laymans terms My understanding is there is no electricity at the socket until its needed there.

Or in other words.

Plug an extension lead in one socket an unravel the whole lead and at the end there isn't any electricity.

Until you complete the circuit. Then electricity flows down the extension lead to the end.
 
The reason the switch is there is to isolate the socket, and anything connected to it, as a safety reason and as a means to cut power to anything plugged into it. He's talking rubbish.
 
There is some minor usage if yu have switches that have LEDs to indicate they are on.
If I remember correctly they do use a few KwH if left on permanently over a year, so that would add up to maybe 30-60p per socket.
You would need a lot of sockets, with LEDs, switched on in your house however to get to the £50 though

Checking the net however it seems thats overstated by a factor of about 10, so a LED in a socket (to indicate switched on) should be less than 10p per year even if on 24/365
 
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Could you find out what univeristy he got his engineering degree from? It seems their course material might be lacking somewhat.
 
robskinner said:
There is some minor usage if yu have switches that have LEDs to indicate they are on.
If I remember correctly they do use a few KwH if left on permanently over a year, so that would add up to maybe 30-60p per socket.
You would need a lot of sockets, with LEDs, switched on in your house however to get to the £50 though

Checking the net however it seems thats overstated by a factor of about 10, so a LED in a socket (to indicate switched on) should be less than 10p per year even if on 24/365
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They actually use neon lamps, as they can be plugged straight into the 240V.
 
Only if you have a device plugged in to it, even if the device is not on, it will still draw power. That is why when you plug in ac adapter or 12v converter it always heats up even when it is not being used. Unless the device has a switch on the psu of the device. Like a pc or kettle.
 
Just spoke to the electrician at work if leaving the switch on an unplugged socket used any power and I got this reaction....


But jokes aside, he said no it doesn't and pointed out that switches on plugs are only common nowadays, years ago they didn't even have a switch (like pictured in a post above).

We started talking about leaving things on standby and he said it's really not worth worrying about, he said if you boil a kettle, leave the room for some reason and have to come back in and re-boil it then you've used more electricity with that one action that leaving a TV on standby all day. The only thing he turns off fully (that I don't) is his modem at night but other than that his advice was unplugged sockets use zero power and most things on standby use so little it's not worth worrying about either.
 
It's not just about saving a little bit of standby-power imho.
It's also good safety practice to isolate stuff you're not using especially if they are going to be unattended for a significant amount of time.
Although very rare due to all the safety circuitry and fail-safes in devices these days, it is possible for devices to become faulty and start fires :eek: And when it's so easy to flick a switch I really cannot see the point in leaving devices on when not in use, pure laziness imho.
 
jakedude182 said:
Yeah, Though only power lost from resistance in the form of heat on the cable to the plug sockets, and around the ring.
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Say what???

If there's nothing plugged in then there's no circuit, so no current is flowing, so there's no voltage drop across the ring and therefore no heat generated or lost!
 
C.R.A.Z.Y said:
It's not just about saving a little bit of standby-power imho.
It's also good safety practice to isolate stuff you're not using especially if they are going to be unattended for a significant amount of time.
Although very rare due to all the safety circuitry and fail-safes in devices these days, it is possible for devices to become faulty and start fires :eek: And when it's so easy to flick a switch I really cannot see the point in leaving devices on when not in use, pure laziness imho.
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You can't just say 'pure laziness' as a blanket statement though. My 32" LED TV doesn't have a power button, it's standby or on and that's the only two options. For me to remove even the standby element I'd have to clamber round the back of the unit and physically unplug it (and again to plug it back next time I want to use it again).

Now I see energy as a trade off, for me to totally turn my TV say every night and when I go to work the amount of my energy (which comes from food which is a cost) would outweigh the electrical energy I was saving.

As for the safety issue, I'll unplug everything if I'm going on holiday but that's the only time. My house has a pretty sensitive circuit breaker and the slightest hint of abnormality and it trips, which if anything can be quite annoying sometimes like when my washing machine went wrong.
 
Heh, I have a full reptile room, with plenty of heat mats, ceramic bulbs, flourescent strip lights both in canopies and clipped onto the back wall, and a misting system with pump and valves. Thats also in the same room as my server + related equipment.

Its all on 24/7.
 
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