Electricity consumption on standby

[Martin963]

This season I've noticed that our electricity consumption seems to be a bit higher than usual,  and to cut a long story short I decided to do some sleuthing.

Unplugging everythig obvious (such as fridges,  depp freezes,  lights etc) left a running consumption of 260 W (370 if you look at the reactive figure) as read off our EDF meter.

Well that shook me,  that's 1 kWh consumed every four hours,  that's 6 kWh a day costing about 30 p daily.  Over a summer that's £54.

Further unplugging revealed that the computer on stand by (with a few other things like a minidisc recorder,  ADSL box etc) was consuming 30 W.   A hifi system (with the amp on to pass audio from a sat box to a (hem hem) FM transmitter was using about abother 90 W,  another sat system + TV in standby  in the kitchen was using 30 W.

But the shock was that the microwave (which is what I got the final tranche narrowed down to) was using 40 W (90 W reactive) just sitting on the counter.

Now I realise that at low levels the EDF counter is likely to start showing erroneous figures,  but this is still pretty worrying.

Some of our increase this year is due to having obtained ADSL;  instead of waiting until 7.00 pm to go onto dial up (when it got much cheaper for us) the computer is switched on in the mornings for me to have a quick peek at the internet (and of course the fine folk on this forum) - this tendency has not been helped by the dreadful weather this summer that has made the computer an attractive alternative to going out and battling with our 12 Ha in the rain.   Even though the computer is switched to go off after a period this has undoubtedly pushed up our consumption.

But the point of this post is that I have been wasting a fair bit of money, and whilst very little CO2 has been produced (as 85% of France's electricity is produced by nuclear fission) I'm hardly doing my bit for the environment in general.

So the microwave will go on a switched adaptor,   a way will be found to bypass that elderly amp so that sat audio goes direct to the (hem hem) transmitter,   the computer settings will be further reviewed,  etc etc.

I post this because I have - even as someone relatively technical - been shocked by the findings.

[Tim]

Interesting post Martin and something, as a naturally born skinflint, I've been interested in for some time. Although I've not gone as far as your in depth investigation, I've also been well aware of the consumption of many household items when left plugged in, but not switched on.

One thing I've done to try reduce the leccy bill is to use one of these switched extention leads for for audio/video equipment so that the whole lot can be easily switched off when not in use, and I usually do this every night. I've also got this type of set up in place for the computer equipment with the ASDL modem on a separate switch so that it can be switched on for the laptop in another part of the house.Incidentally, leaving the modem on has been talked about on here before and I've never had a problem with turning it off when not in use.

Of all the items you mention though, it was the consumption of the microwave that intrigued me the most. I always unplug ours when away for more than a couple of days, but I will certainly be paying more attention to it now. I may even go as far as looking at the manual to see if it gives any power consumption figures.

Tim

[Clair]

I recently purchased an energy monitor to assess the electricity consumption of the various households itmes both in the gite and at home (I did not pay that much for it though!):

http://www.conrad.fr/

I was happy to see that my usual wash @ 50º  at low rate was not as excessive as I feared and that even 1 hour of drying towels at low heat and low rate was fine too.

I still have to check on the hot water tanks and I will make a point of checking the microwaves

[Martin963]

I still find that microwave figure unbelievable,  and when we come out next year I'll bring our energy monitor with us from the UK to see if it gives the same figure.   However it was the case that the 40 W (90W reactive) reading vanished off the meter when I pulled the plug on the microwave.

Of course I suppose one should save as much as possible,  but in a way turning things off at night is less tempting when the "heures creuses" are in action for most of the time one is asleep.   As Clair says,  tumble drying is NOT that expensive if used sensibly,  and the dishwasher on at night is also very very cheap (and we use next to no detergent as in our area the wash is fine on a level teaspoon of powder - I'm convinced that the ads for dish washer tablets are a con for most people as they will be designed for hard water areas and often you could get away with one quarter of what they tell you -  hence we always buy in powder form,  better for the septic tank too!)

It's just so annoying that so many gizmos (particularly DVD recorders,  sat boxes,  ADSL boxes) are computer based and therefore seem to spend a good two minutes scurrying about wondering what's hit them if you turn them off when not in use.    Whcih is a pain if you rush in and miss the headlines because the box is doing its run-up.

[Martin963]

Further to the microwave consumption,  I think we can assume that it is exaggerated by the meter.   Having tested it in a slightly different manner (by putting a low load onto the supply (250 W) and then ADDING the microwave by plugging it in) it does not alter the non-reactive figure at all,  while it pushes up the reactive figure by 30W.    I suspect that the EDF meter is only giving a rough figure at vanishingly low power levels and is being thrown by the fact the the microwave in standby is presenting a very uneven (from a reactive point of view) load.

Having said that,  it's likely that the general standby figure I gave is much more accurate,  so whilst I shall rule the microwave out as a major culprit the other modifications are in hand!

[Gyn_Paul]

Martin,

Sounds like next time we have a rainy day you'll be getting out the

soldering iron, a couple of flying leads, a plug and socket, and the

multimeter to construct a bodgebox to enable you to measure the actual

current of any appliance you care to plug in.

One of the disadvantages of having the electric meter in (what is

currently) the living room is the fact that you catch sight of the

flashing mimic strobing at you when everything kicks in on the HC

setting. Equally, as I go round the place last thing at night turning a

million lights off, the computer, the TV (et al), I notice there is

still quite a regular flashing from what's left. So you're not alone in

wondering quite what is sucking up the power when  - ostensibly -

there should be nothing left working.

p

One thought struck me from your observations: If the digital meters are so inaccurate in their readings of low currents; are they equally inaccurate when it comes to charging, I wonder ?

[Martin963]

that thought (accuracy) struck me too,  but was too ghastly to contemplate!

But actually the advantage of a meter with flashing light (as you have now in your (new - you moved didn't you?) place) is that it must act as a good incentive to switch off....

[Gyn_Paul]

[quote user="Martinwatkins"]that thought (accuracy) struck me too,  but was too ghastly to contemplate!

But

actually the advantage of a meter with flashing light (as you have now

in your (new - you moved didn't you?) place) is that it must act as a

good incentive to switch off....

[/quote]

...depends on your definition of 'new' - we will have been here 3 years

come Feb and we've only just got our P de C sorted out. Congenitally

lazy, that's us! Mind you, the renovations we've designed into the

plans now, are entirely different to those we'd have gone for 2 weeks

after we moved in.

a good incentive to switch off...       well yes, except that (at that time of night) I usually can't think of anything I've left on!

p

  

[Gyn_Paul]

I now have a little gadget which measures the electrickery whizzing

through it, and my hifi/tv stack, I discover, gobbles 45w in standby

and 190w when the lot is switched on.

I'd dis the plug last thing at night except that the DVD recorder has a

fit of the vapours if it loses its volts and insists on doing a full

disk scan which takes it about 4 minutes. By which time I've missed the

plot of the thing I'm trying to record !

Just out of curiosity I'm going to go round the house and see what else is hogging the 229 volts (I know, sad git).

p

However I'll need to find my strongest £-shop reading glasses to see the results, the screen is about the size of a Xmas stamp

[Racerbear02]

I just bought an electricity meter from ebay, similar sort of thing to the one from conrad but cost €13.60 +postage item 120170090961

Delivery was very quick and efficient, I now am about to find out the truth of power comsumption.

[Philouis]

We have a upright floor standing lamp rated at 900w. It has a dimmer switch and thinking to we will save electricity, we turn it half down. But something I read recently hinted that when the lamp is dimmed, the power consumption stays the same, as the dimmer eats up the power the lamp bulb is not using. True or false?

[Gyn_Paul]

I take it you're in Devon, Martin.

p

[Martin963]

Yes -  like the swallows but in the opposite direction;  we've only just got back.    Not that I've located my consumption meter yet.

It won't be today,  I've wangled an invitation to Stockland Hill (I'm sure I don't need to explain to you!) to inspect the DSO work going on there at the moment....

[Pierre ZFP]

[quote user="Philouis"]We have a upright floor standing lamp rated at 900w. It has a dimmer switch and thinking to we will save electricity, we turn it half down. But something I read recently hinted that when the lamp is dimmed, the power consumption stays the same, as the dimmer eats up the power the lamp bulb is not using. True or false?
[/quote]

False!!

What the dimmer switch is doing is clipping the waveform of the alternating cycle lec-trickery feeding the lamp.  In other words, the voltage on each cycle would normally rise to its maximum positive value then fall to its maximum negative value 50 times a second (this is do much easier to explain with a picture). The dimmer, using transistors (actually a thing called a triac), will switch off the current at a pre-set level on each cycle thus dimming the lamp.  It does this so quickly that you won't notice a flicker, well maybe at very low levels. So, less light output, less power consumed.  Because nothing is perfect, the dimmer may waste a little energy in heat but this is negligable.  Dimmers also possible for flouresent lamps but these are a bit more sophisticated.

[Gyn_Paul]

[quote user="Martinwatkins"]Yes -  like the swallows but in the

opposite direction;  we've only just got back.   

Not that I've located my consumption meter yet.

It won't be

today,  I've wangled an invitation to Stockland Hill (I'm sure I

don't need to explain to you!) to inspect the DSO work going on there

at the moment....

[/quote]

Not the location, but perhaps DSO ??

The only time I ever went to Stockland Hill the ground didn't emerge

from the fog until about 2.30, and even then I had to take their word

for it that the mast actually had anything on the top of it.

But then I am a bit like the lorry driver - a Douglas Adam's character

- who spent his life driving in a permanent raincloud because he is

actually a rain God. We spent 5 weeks holiday in southern Germany one

year and I never once got a clear view of the top of a mountain.

We expect a full report when you get back. Have fun[:D]

p

Edit:  just worked it out. Digital Switch Over. Of course. Excuse the fog-addled brain.