Owl Energy monitor - how accurate?

Madfish

How accurate are the owl monitors, i just got a C119 model that gives a history of what KWH you are using, after taking a note of my meter and letting the unit run for 15hrs my meter had used 3 1/2 units more than the owl had recorded. I can except there will be a slight difference but thats a lot of usage in just a short time.

The meter is brand new (last tuesday) so do you think its faulty? if not the energy monitor is pretty much a waste of time....

Magentasue

Over a week, our Currentcost records three or four more kwh than we've actually used (normally 90-120 a week).

mark55man

have you set up the volts properly - mine was set at 230, but measured at the wall at 242.

I don't know the calculation in detail but Power = Current * Volts so as OWL works on current variations (thats what it detects) therefore if your OWL is underreading that would suggest it is configured at a lower voltage than is actually happening

mark55man

Also, even if it is marginally inaccurate, it is still very helpful in reminding you when you have lights on that should be off, after all if all you used it for was to tell you the meter reading you don't need it!!

Alan_Vickers

I have been using an Owl monitor for just over four weeks now and have taken simultaneous weekly reads on the Owl and on the electricity meter. The Owl has been reading high by between 3 and 4.5%.

Madfish

Thanks for the voltage tip, yes it was set at 230v, I have changed it to 240v so hopefully it'll be about the same now, and yes I agree even if its marginally the same at least you can tell what needs switching off etc and keep an eye on energy costs, not that its too hard to work out via the meter but at least you know its correct.

One thing I am annoyed about is that we swapped from a pre pay meter 2 weeks ago that was already in the house when we moved in and have been paying £30 approx every 12-13 days, now with the standard meter we have only used about £20 in the same time, even accounting for the standing charge and slight unit price reduction I reckon the pre pay was definatly mis reading, guess its too late now.....

mark55man

like I say - not sure about the maths of it all, but if it helps you to line your figures up then adjust the voltage - if the owl is reading more than your consumption then reduce voltage setting, and vice versa.

can anyone explain why the national grid ambient voltage seems to vary??

ronald208

I have been using the Eon version which seems to be a rebadged Current Cost for a few months and mine gives readings less than my electricity meter.

I use about 13Kwh of electricity a day but when it gives the daily and monthly usage it gives 10Kwh per day and 31Kwh per month.

During the night it gives a reading of .072Kwh but it is under by about .025Kwh when I checked my meter by reading it when I went to bed and got up in the morning. I got some funny looks from a neighbour when she saw me reading my outside meter in my dressing gown. I wanted to check before I had my shower and put the kettle on for my coffee.
Also the clock loses about 3 min per day.

I phoned Eon about it and all the person said was that it was for guidance and was not all that accurate and my electricity meter was more accurate. I turned everything off and turned on a 2Kwh kettle and the reading was 1.893Kwh so it is reading under.

I do not think it is a waste of time even although it is not 100% accurate as before I got it I was using 16Kwh of electricity a day.

I went around the house switching things off to see how low I could get the reading before I went to my bed, it went from from .200Kwh to .072Kwh.

Since I have got my electricity monitor I am saving about 40p a day, which is £145 a year all from stuff that was left on unnecessarily during the night or on standby.

Ron

Garetha

ronald208 wrote: »

... I turned everything off and turned on a 2Kwh kettle and the reading was 1.893Kwh so it is reading under. ...

The 2Kwh kettle only uses 2Kwh at the standard voltage.
If your voltage is lower the kettle will use less.
Voltage differences are due to local circumstances and will vary by small amounts from minute to minute.

wolvotim

Your supply voltage depends upon lots of different factors such as circuit loading, size of cable, distance from sub-station. Most homes (as long as your not fed from the same sub-station as a factory with large machines) should be around the 238ish mark. UK mains voltage is 230 +10% -6%