My advice would be to track down what's using that electricity by turning things off. I would switch each circuit off in the consumer unit until you find the one that's causing the problem. Then track down everything that's on that circuit.

Hi @edgood

I think the idea from @M.isterW is a good one.

Is your hot water electric?

Are you sure you don't have an immersion heater in your hot water tank permanently on? You probably have a separate circuit for this in your consumer unit. Try turning that off? 

Always on appliances that can go wrong include fridges and freezers, even relatively new ones. It would be worth checking the out the fridge freezers when you are doing the general checks.

You are right 12000kWh is a lot of electricity, especially for someone with gas heating. Definitely something wrong if that is the amount. Ofgem quote a typical domestic consumption value of 2900kWh a year for electricity. In fact 12000kWh is the ofgem typical consumption value for gas. 

Hi Jeffus and M.isterW,

Thank you both for your responses. 

The hot water system is powered by gas. There is an immersion heater, but this has never been turned on. I turned off fridge-freezers over one night and this made no difference. I also switched off the MVHR system last night, to see if that was the issue - it wasn’t; power continued to be used throughout the night. 

I will now try the suggestion to take a whole circuit at a time using the consumer unit. 

This is a mysterious one @edgood 

Are you able to post any graphs of the daily usage profile that show the spikes? Does your OWL monitor allow output in that level of detail, or are the spikes getting lost within each time band? 

How does the 30 minute output info from your smart meter look in comparison? Anything you can post here may help eliminate some options.

@edgood 

The extreme is to turn off all the circuits for a short time. Take a reading at the start and end. Just to also double check your meter isn't ticking over with what looks like zero load.

Thank you all for suggestions, which I will try.

Re graphs.  The Owl monitor graph below shows almost a two day period this week when we were away. Heating and hot water systems were turned off. 

The left side shows a spike in the morning, about 8pm, when we had coffee and then left the house. From then for the whole of the day (22 Oct) and the next, until we returned around 16:00 on 23rd, the graph shows a continuous pattern of usage. This usage amounts to around 15 kWh per day when we are not in the house or using any appliances, other than the fridge-freezers and MVHR (both of which I’ve checked to see if they are the culprits.  (When we are in the house, the average usage leaps to an average of 32 kWh per day, for a total (electricity only) of just under 12,000 kWh per year).

In the valleys between the spikes the usage is at a rate of (consistently) close to 0.9 kW. At the peaks the rate of consumption rises to between about 2.3 kW and 2.5 kW. The peaks tend to be very close to 30 mins apart.

 

We like a puzzle ! You say your immersion has never been turned on, but is there any chance it actually is permanently on ? What kind of control does it have? When did you first notice this high electricity demand?

Can you get a more detailed chart from the OWL? That shows consumption over a few hours rather than several days. Then we can see how long the spikes last.

Also, 900w is a really high base load. Ours is 200-300w and we have two fridges, two freezers and a gecko to keep warm.

900w would be 21.6kWh a day…

That is extreme and would point to it potentially being nothing to do with the short spikes if it really is anything like that high. 

I would try the meter creep test then by turning everything off at the consumer unit and seeing if the meter still ticks over.

Then when you test each circuit as has been suggested , look out for anything that might have a high standby power due to an error or normal operation. 

Do you have any pumps in your heating system that have been wired to run permanently by design or mistake? 

Just as an example here are our 30min slots from a night. 

This is probably a daft question but you don’t have an Electric Aga cooker by any chance?

Thanks again everyone - I’m glad you like a puzzle!. Here is a zoom in from the whole graph (ignore the 1W in the time frame).

This has been going on for a long time and I have been trying to get help from our electricity supplier (not OVO!).  I tried the creep test - all OK. I asked for a meter test - they procrastinated for months and finally a man with a cheap fan heater arrived and a clip on monitor (similar to an OWL). He spent about 30 mins or so and said I would hear - four weeks later and no news, so I bought the OWL to check myself.  (The meter “test” was not done at all in the way that government guidance suggests. I have of course tried the customer help line, but their responses (average 1 week response time) show that they haven’t even read my emails! (end of rant).

I hadn’t really realised how high our energy was as I was an expatriate for many years before moving to this house - I was 30 years out of date with UK utility matters! Of course, with the increase in energy I became extremely interested.

Re other questions: The immersion heater has a dedicated wall switch beside the storage cylinder.  I will check now - as has been suggested - that it doesn’t simply bypass this switch.  I think the best way will be to turn off that circuit in the consumer unit.

I guess the other possibility is the pump serving the Underfloor Heating - I’ll check that as well.

Not a daft question - but no, we don’t.  

Over on the E.On Next forum there has been a case where anytime some energy is used the meter records 2kW as a rate of consumption - never more never less.  After looking into all the possibilities, just as has been done here, the unlikely diagnosis was a meter fault.

I would enquire whether another meter can be installed as a check on the first.  This case has some of the same characteristics -  a high base load and peaks of even amplitude.

Very high base load, so its case of working out what it is. I’ve got fish tanks and pond equipment running and my base load is 200W. 

Turn everything off, power the OWL meter via batteries and take it turn to switch back on circuits (fuses) in the fuse board, looking for one which is drawing 800-900W.

Check the OWL readings by turning on the kettle and making sure the use increases by 3kw.  

What MVHR do you have? Some have electric heating elements in them to temper the air.

Other suggestion would be external halogen lights / loft lighting.

I’ve used KASA smart plugs (not all of them have energy monitoring) to check devices.

Far out suggestion would be that there is a connection to your neighbouring property, either unintentional (new build horror), or malicious to cut their energy bills. This would show up as a high load on one circuit, but nothing in your property (on that circuit) turned on.   

Thanks for this - unfortunately my supplier has basically refused to install a check meter. I asked that they do this and take the existing to an independent lab (as they are supposed to do) for testing. This is why I bought the OWL.  Your reasoning seems very good to me - I’ll have another go at them.

“What MVHR do you have? Some have electric heating elements in them to temper the air.

Other suggestion would be external halogen lights / loft lighting.” 

MVHR has no heating elements in. All lights are LEDs (permanently on outside lights are, in any case, forbidden in my dark skies are.

It could be your smart meter but your OWL sensor is also picking up a high kWh so it is not simply the smart meter recording a high usage, you appear to really be using a high kWh?

Could a smart meter be actually drawing a high kWh when under a small load? I doubt it but you could test by turning off all but one circuit and adding a small known load. You could do this when testing each circuit as suggested. 

This is better than the telly !

Thinks outside the box (or house).

Is the house terraced or a semi?    If so,  how well do you oknow the neighbours?

It has happened before that a neighbour manages to tap into one of your circuits and uses it to power so called “ illicit activities”.    900W - could easily be the load for heat lamps being used to raise plants.

Once you find out the circuit that is using the power,  you will then need to find the appliance or device and if all of yours are off and power is still used, you will need to dig deeper.

Thanks. The house is detached and about 30m away from the neighbours. I don’t think they have a cannabis farm, but one never knows! However, when our house was built the same meter was used for the two properties on the site as they were both owned by the same person. There was confusion on completion of the house, but I do think they did separate the supplies! I tested this by turning off our supply and then checking if that had also turned off the supply to the other property - it hadn’t.

Hey @edgood,

Welcome to the OVO Online Community!

This is a really challenging one. Given all the information you’ve provided, I’m really surprised your current supplier won’t install a check meter? Do they allow you to book one if you pay for it?

I’d advise following the suggestion of checking each circuit, also you mentioned underfloor heating… it’s worth looking into whether this might be the issue.

Please do keep us posted, this could really help other customers in a similar boat. 

I don’t think it’s a meter issue personally. When you had the meter checked were you asked if you’d like the results of whether the meter was within acceptable tolerances confirmed in writing? It would be useful to see the summary of this. If this was with the supplier you mentioned the quickest response is likely to be via Twitter direct message, if you use that.

Going back to basics, I’d turn absolutely everything off for 30-60 minutes, if you can, just to confirm that the meter isn’t picking up any abnormal usage. If it is then we really do have a puzzle.

Your comment about a shared meter still makes me wonder.

Work round your house and turn OFF every socket, switched spur, light, heating - EVERYTHING including fridge/freezers which will survive for a few hours.      But leave all the breakers and main supply on.    Wrap up in blankets with your torch and charged mobile for company - or go to teh pub!       

Check teh meter at the start and then after 1, 2, 3 hours - how much has been used?    It should be ZERO.       Then get back to normal.

If it is ZERO you will need to find out what device is causing it.   If it is greater than Zero,  then power is going outside your house.

Finally my issues were taken up by an excellent team leader, who acted very promptly to locate the result of the meter test. This showed it was up to around 8% inaccurate, with some variation between the three tests done at the same appointment. They will replace the meter with a SMETS2 and IHD and refund me for overpayments in the past.  This, of course, only accounts for a small part of our consumption, but it is a start!

I took  the suggestion from juliamc  re the possibility that the immersion heater was wired directly and not through the dedicated switch and turned that circuit off, last night at the consumer unit.  Coincidence or not, the half-hourly spikes disappeared and only two spikes were recorded across the whole overnight period. I’ll see if this continues.

I’ll start to do the wholesale switching-off of circuits when my wife is away for the day next week!

It looks now as though the heavy consumption is due to a range of issues - I am sure with the excellent suggestions on this forum, I will track down the problems.

Not a bad result then! It sounds like you’ll also get the £160 test fee back as well.

Just thought I’d let you know that it may take a few weeks for OVO to validate exactly how much to refund and make the arrangements, but you’ll know when it happens. The end result is that for the most part, you should be put back in a position you’d have been in had the existing meter been accurate.

8% inaccurate is quite substantial as well! 

Thanks Blastoise186  I have to point out that I am not with OVO. The previous poor responses were from another supplier. They don’t have an excellent forum such as this