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Firedog
Super User
Super User
February 26, 2024
Solved

Why is my Future Annual Consumption estimate so persistently high?

  • February 26, 2024
  • 86 replies
  • 1895 views

I have just read this passage about FACs in another thread: “… my own experience shows that [the future annual consumption figure] is being based on, (or at least being adjusted based on) actual meter readings. I could see my FAC for gas changing (reducing by large amounts) within minutes of submitting a new meter reading.”

This is what is supposed to happen, if I understand the wording here: Usage projection is a figure produced by our billing system, that uses smart meter readings (if available) to project the usage for you over the next year.

We clearly have a two-tier system: an ineffectual one for smart meter customers, and another better one for everyone else. Those who submit manual readings 'see their FAC changing within minutes.' Those of us with smart meters are apparently subject to a system which can take months to adjust the FAC to actual usage, despite having meter readings recorded automatically every day.

My own (electricity only) FAC got stuck last year after a meter adjustment. I was told last year, as was the Ombudsman, that it would all come right after a meter exchange, which happened in September. There was no change to my FAC until mid-November, when it suddenly started falling from its figure of 2.35 times the actual annual usage. This is how it has progressed, from its stubbornly-maintained figure of 2902.9 where it had been since the previous April:

 

 

I can't explain the hiatus in early January, unless there was some manual intervention. The figures are updated every Sunday, and occasionally midweek: there have been 16 updates since 5 November. If manual intervention is possible, then there’s no need to rely solely on this clearly flawed system.

I suppose I should be grateful that my FAC is now only 76% higher than my actual consumption for the past year. Excel tells me that if both curves proceed at the same rate, they will eventually meet on 8 August next, just one year after OVO assured the Ombudsman and me that a meter exchange would soon solve the problem.

For those of us with multi-rate tariffs (e.g. Economy 7), there have to be FAC figures for peak and offpeak usage. It’s the ratio between these that determines how economical the tariff is, so it’s also important that this ratio is also accurate. It’s not, for me. Not only is any Direct Debit calculation worthless, but so are projected costs when trying to compare tariffs. 

There is something seriously wrong with the FAC determination if it can't adapt more quickly to actual, readily-available meter-confirmed data as Ofgem mandates and as Tim maintains it should.

Best answer by Firedog

Updated on 15/08/25 by Emmanuelle_OVO:

 I’ve now (courtesy of @ChristopherS_OVO - thanks!) had some actual figures for the calculation of my FAC, and they’re as clear as an early-morning midstream sample. I learnt a few things, though:

  • The EAC is indeed allegedly updated to reflect data shared by the supplier. If that sharing fails for some reason - and it clearly did in my case - the EAC reverts to a default value, subsequently adjusted for whatever data have been successfully shared since the fault. 
  • I can’t for the life of me work out where these default values come from. I’m told they are for a ‘typical E7 user’. So no attempt at all to take into account the factors that Uswitch and comparethemarket say are used to match the EAC to the user’s household [“central industry sources including the Retail Energy Code Company … estimate your consumption over the next 12 months based on a number of factors about your property and based on your property’s historical consumption.Your usage comparison is based on your energy usage compared to other households in your postcode region. Your usage will be affected by a number of factors including the size of your home and the number of people who live there.”]
  • Meter readings are thus used to adjust the EAC from its initial default value, but this can only happen of course if OVO successfully submit readings. This seems to be where the fault is in my case.
  • OVO then generates an FAC from the current reading and the current EAC, the proportions of each depending on the time elapsed since Week 0. By Week 52, the EAC proportion will be 0 and the meter advance 100%. 
  • It’s impossible for me to work out how the EAC is adjusted when a reading is submitted, but I suspect it’s a similar arrangement.* This being the case, the FAC should approach parity with the meter advance before the year is up. How long before is a mystery, but it’s not likely to be nine months before.
  • I can see no reason why OVO can’t generate a more accurate FAC if it’s clear that the EAC is wrong. OK, this would involve manual intervention, which they understandably try to avoid. However, I’m sure it would have taken much less effort on their part just to do this rather than involve at least five different employees in trying (and failing) to explain why it went wrong for me in the first place.
     

[I just realized after reading this through, though, that this was the sort of approach Fujitsu took when faults appeared in bits of their Post Office Horizon system. I won’t draw any more parallels ...] 
    



*   If it were a similar arrangement (the EAC value changing pro rata with the meter advance over a fixed period), then we’d end up with a second-order function which would give a parabolic curve if the actual consumption was lower than expected. Something like this (I know how you all love my pretty charts 🙂):
  

 

86 replies

Firedog
Super User
FiredogSuper UserAuthor
Super User
May 7, 2024

Apparently Xoserve have the wrong MSN listed for me.

 

I’m surprised that this isn’t one of the first things to be checked when there’s an inconsistency involving submitting and retrieving data from an external database.

  

As your issue also appears to involve a (electricity) meter exchange then if you haven’t already you may want to check whether Elexon have your MSN correct for your electricity meter.
  

I was told that there was at some stage a ‘validation failure’, so the third-party data collector concerned was asked to investigate and resolve the error. That was on 1 March … 

 

Noel | I have no official status; I'm just a volunteer who comes here to help other customers. My gear: Aclara SGM 1416-B Electricity-only E7 meter; Chameleon IHD3-PPMID-AAA | It may look as if I know what I’m talking about, but don’t let that fool you. |
Nukecad
Super User
Super User
May 7, 2024

Apparently Xoserve have the wrong MSN listed for me.

 

I’m surprised that this isn’t one of the first things to be checked when there’s an inconsistency involving submitting and retrieving data from an external database.

 

I was also pretty surprised myself.

Particularly as I had made two previous complaints to OVO about them having the wrong MSN showing on my account following the failed exchange, the first in July 2023 when they corrected it, then I had to complain again in November 2023 because someone had ‘helpfully’ put it back to the incorrect one.
(So I do in fact know both MSN’s involved, the correct one and the ‘never fitted’ one).

It appears that although OVO had finally got the correct one on my account they hadn’t informed Xoserve of the error.

Silly me for expecting them to do the job properly I suppose.

I said, Hey - Watts going on.
Firedog
Super User
FiredogSuper UserAuthor
Super User
May 11, 2024

 A couple of weeks ago, wondering why my FAC started from such a high value, I wrote “2700 kWh is the TDCV for a medium-usage household. A quick glance at my history would have revealed that my usage is consistently less than half of that, so I wonder why the low-usage figure (1800) wasn’t selected, if they couldn’t use the actual consumption figures for my MPAN.”

Since then, Christopher remarked:  ‘… when we know there is an imbalance in the calculations ... There are some occasions where the imbalance is necessary such as a meter exchange as the system would in a way treat this as a “fresh start”.’ 

Yesterday, wondering why my DD calculation can’t be put right, I read in OVO’s own help article that “If you’re new to OVO, [fresh start?] we work out your Direct Debit amount to cover your expected energy use over the next 12 months. We base it on your past year’s energy use if you know it.

I know it and I knew it down to the nearest 0.001kWh, yet nobody asked and no-one will listen when I point this out. This is gross discrimination against existing loyal customers as opposed to new ones. 

Any comment, @ChristopherS_OVO?

 

Noel | I have no official status; I'm just a volunteer who comes here to help other customers. My gear: Aclara SGM 1416-B Electricity-only E7 meter; Chameleon IHD3-PPMID-AAA | It may look as if I know what I’m talking about, but don’t let that fool you. |
Rank 2
May 12, 2024

My FAC has been an interesting work of fiction from day 1. 

As, presumably, this is the figure used to determine direct debit payments,  I eventually decided to pay monthly for actual usage. 

Additionally, based on my overall experience with OVO, I would not want OVO to have the access to my bank account that a direct debit permits.

 

God help OVO and all who sail in her! The Neat Heat trial has ended. I still can’t leave OVO for my preferred supplier, because they’ve messed up my opening meter reading a year ago. Ombudsman informed.
Chris_OVO
Community Manager
Community Manager
May 13, 2024

Hey @Firedog,

 

I don’t have a comment sadly as we’re here to moderate the Forum and create content. I’d suggest if you still aren’t happy with the way the FAC is calculated that you follow the complaint process and raise it as a complaint that can be investigated through the correct channels. You can find our Complaint Handling Statement here, https://bit.ly/3DcsZdj, along with more information on our complaints process here: https://www.ovoenergy.com/feedback.

 

I’m sorry there isn’t more we can do to help you here! 

Renewable energy jokes never get old.
Firedog
Super User
FiredogSuper UserAuthor
Super User
May 21, 2024

Thanks, @ChristopherS_OVO. I wasn’t expecting any sort of authoritative statement, but I suppose I was just a bit peeved to discover that new customers are taken on their word when they say how much they used in the past year while loyal ones like me aren’t. Not to worry. As you’ll see, my FAC is inexorably pursuing its glacial path to a reasonable sum in a few months’ time. I’m just hoping that my chat with Support about my DD a few days ago will keep them off my back until that happens.

 

 

Noel | I have no official status; I'm just a volunteer who comes here to help other customers. My gear: Aclara SGM 1416-B Electricity-only E7 meter; Chameleon IHD3-PPMID-AAA | It may look as if I know what I’m talking about, but don’t let that fool you. |
Firedog
Super User
FiredogSuper UserAuthor
Super User
May 21, 2024

Just a wee update. After veering off-course for a week, my FAC is back on a new track. The total has resumed its gentle decline after its eye-catching side-step, while the peak/offpeak split has taken an altered path:
  

 

With the offpeak FAC is now down to less than a third of what it was in January, it’s still almost three times the meter advance. Any tariff comparison on the basis of these figures is meaningless, and the recommended DD is still £10 a month more than it needs to be.

Hey ho.

Noel | I have no official status; I'm just a volunteer who comes here to help other customers. My gear: Aclara SGM 1416-B Electricity-only E7 meter; Chameleon IHD3-PPMID-AAA | It may look as if I know what I’m talking about, but don’t let that fool you. |
Nukecad
Super User
Super User
July 22, 2024

Well here we go again - Today my FAC for gas has suddenly rocketed up again.

This afternoon it was showing as 9503 kWh, I submitted a new gas meter reading (nothing unusual just a regular months usage) and this evening the gas FAC has jumped up to 14431 kWh.

So it's now at least 50% higher than it should be. (and in reality it's more like 75% too high).

My actual gas use for the last 12 months to the end of June 2024 was 8270 kWh.

Of course this error has also resulted in my recommended DD amount also rocketing up again, by an extra £27 a month.
So no doubt I’ll be getting an email saying that they will be increasing it even though it’s wrong.

It's getting a bit tiresome having the recommended Direct Debit amount increase itself to ridiculous levels again every 3 months or so, and then having to yet again explain to - read argue with - a support agent about why it’s too high and what it should be,

There are a couple of excuses I can think of that could be used to explain this sudden new FAC spike, but neither one very convincing as anything other than an excuse not to look for and fix the real problem.
Either way it shows they are still getting/using the wrong information in the FAC calculation.

PS. My FAC for electricity is in agreement with my actual electricity use, no issues there.
it’s just my gas FAC that keeps jumping up for no real reason.
I put that down to the electricity being smart metered, so it’s time for me to emulate a smart gas meter again by sending weekly or even daily gas readings to get the gas FAC down again.

I said, Hey - Watts going on.
Firedog
Super User
FiredogSuper UserAuthor
Super User
July 24, 2024

  

 My FAC for electricity is in agreement with my actual electricity use, no issues there.

 

Lucky you! Mine is still SNAFU.

While the FAC reported on my Plan page and used to calculate my recommended DD is still falling gently, it looks as if it might meet my actual annual consumption a few days before the anniversary of the meter installation - so much for ‘in three months’ or even ‘within six months’.

A couple of other things are slightly worrying:

  • I had a look at some competitive tariffs. The sites that could be persuaded to use ‘data from trusted industry sources’ to find my FAC came up with a figure of 2786 kWh/year. Compare with my actual annual consumption, which to date is 1050 kWh. Consumption in 2023 had been 1180 kWh. Where are these ‘trusted sources’ getting their figures from?
  • These sites used a day/night consumption ratio of 58/42, which is the Ofgem standard. My current ratio is of the order of 86/14, so any estimates of annual cost are miles out when comparing E7 tariffs.
  • I used to be able to find the current FAC’s day/night figures on the Renewal page. That page is empty for me (“Sorry, there aren’t any plans available for you to renew at the moment”) and has been ever since I switched to a fixed-price tariff more than two months ago, so I’ve little idea what split my FAC is currently based on. I can estimate it from the reliable figures I had stored away before the renewal page packed up, but it’s so far out as to be of no use. Can you see alternative plans?  

The whole Future Annual Consumption / Estimated Annual Cost business was mandated by Ofgem many years ago so customers could make sensible decisions about competing tariffs. I’m sure it’s fine when it works, but it’s intensely frustrating when it doesn’t. I’m even wondering whether the updates OVO is sending to correct my EAC are going to the wrong place like yours were/are. I’ve forgotten - how did you find that out? 

 

Noel | I have no official status; I'm just a volunteer who comes here to help other customers. My gear: Aclara SGM 1416-B Electricity-only E7 meter; Chameleon IHD3-PPMID-AAA | It may look as if I know what I’m talking about, but don’t let that fool you. |
Nukecad
Super User
Super User
July 24, 2024

Because you have fixed then you won’t now see any offers on the  renewals page until it’s 50 days or so before your plan end.

And of course if you use the quote webpage instead then, although it says OVO already supplies the property so can give a more accurate quote, it’s still not going to show your actual usage figures.

I think that you should be able to see some split day/night FAC figures in the DD calculator API.
Mine shows each coming months predicted usage figures for both Electricity and Gas in seperate sections, (and then a secion for Bolt-ons), I would imagine it’s similar for your day/night split.
However you’ll only see the figures for the months remaining on your plan. (The months already past just show as 0).
Mine only shows the one combined total figure for predicted yearly, and TBH I haven’t checked. yet, if that a full year or just what’s left to my fix end date.
Note that they are shown in £ and not kWh, but you should be able to reverse calculate it using your tariff rates.

 

My incorrect gas MSN issue at Xoserve appears to have finally been sorted out now.
(Albeit with the added complication of that ficticious account switch which took a ‘Digital Resolver’ (Ben) to fix).

I was considering pushing now for a gas meter replacement to be tried again, my existing one was already too old over a year ago when they tried but the engineer couldn’t get the new one to connect (not sure if it was a HAN issue, or a WAN/DCC issue, I wasn’t as clued up then as I am now) and that’s when they messed up the meter serial numbers.
I’ll probably now try to get the FAC down again first, it’s already coming down following another submitted meter reading; after just 2-days it’s dropped by 646 kWh to 13785, so still a long way to go.

I said, Hey - Watts going on.