Algorithm for calculating annual use

  • retrotecchie's Avatar
    Level 92
    Is there an algorithm that E.On Next use to calculate the forecast energy usage over a year and if so, is this recalculated on a monthly basis or does the 'forecast year' have a fixed date used for the forecasting?

    I cannot see any logic in how my estimated use is actually calculated.

    Here is my latest bill, bearing in mind that December is possibly the month in which my electricity use should be at it's highest.

    Name:  dec bill.PNG
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    You can calculate that for 29 days in December, I used an average of 9.1 kWh a day. Assuming my energy use were to remain consistent, that works out at approximately 3323 kWh per annum, so how does the estimate arrive at 4730.2 kWh per year? As all meter reads ignore the decimals so we're only working in full kWh, why is the 0.2 even there unless whatever algorithm does some very funky maths?

    The estimate is 42% higher than my own projected usage, based on a constant 9.1 kWh a day, which will actually decrease over time towards the summer.

    So how is this estimate actually arrived at?!

    Not that it makes much difference - my usage is what it is so any estimate is somewhat irrelevant in the grand scheme of things. I'm just interested in how it is actually 'guessed'.
    Don't shoot me, I'm only the piano player. I DON'T work for or on behalf of EON.Next, but am willing to try and help if I can. Not on mains gas, mobile network or mains drainage. House heated almost entirely by baby dragons.
  • 9 Replies

  • Matobato's Avatar
    Level 7
    Have you been with Eon for longer than one year and have not had a meter changed? If yes please find a statement from December 2021 and subtract the meter readings. I assume the difference will be in 4700s.
  • retrotecchie's Avatar
    Level 92
    @Matobato

    Been with them since October 2021. The estimate for a year on my Dec 21 bill was roughly the same, give or take. Total consumption for 2021 was about 3400 kWh.

    So, my consumption and usage has dropped a little over the last 12 months but their estimates in both cases are still about 40 percent too High.

    My previous supplier gave me month by month comparisons and the per month energy use was fairly consistent over four years.

    Last edited by retrotecchie; 02-01-23 at 15:38.
  • Mailman's Avatar
    Level 56
    @retrotecchie

    My records (and Eon Next's records) for the year 2022 show that I used exactly 2495 kWh Electricity whereas the latest January 1st bill states a forecast of 2519 kWh so actually not that far out (3 days worth).

    The gas estimate is too low @5220 kWh compared to an actual 2022 usage of 6160 kWh. However the next 3 months might well see me reduce my gas consumption from a 2022 level of 3000 kWh to nearer 2000 kWh in which case Eon Next might be spot on - we shall see. The first 3 months of this winter (Oct-Dec inc) saw me go from 3630 kWh to 2150 kWh so maybe a 2000 kWh for the second half of winter will be nearer the mark as well.

    Whatever the algorithm is, it is not easily transparent for Eon Next customers especially those on fixed direct debit amounts. I know that Shell's anticipated usage seem to follow the pattern of the previous 12 months rather than trying to predict emerging patterns (garnered from in-laws data).
  • retrotecchie's Avatar
    Level 92
    @Mailman

    Just looked at my annual estimates from my last few bills.

    16 October bill guessed at 5396.2kWh.
    29 October bill guessed at 5242.3kWh
    02 December bill guessed at 4843.2kWh
    01 January bill guessed at 4730.2 kWh

    Actual usage for 1 year, 42% lower than their lowest guess.

    The only thing I can infer from this is that they based the annual 'guesstimate' on my June to July consumption, which was a bit higher than average for a week or two as I was doing a lot of DIY in the garden and shed over the summer and giving it large with the power tools.

    As I say, it matters not a jot to me but if the information is provided on the bill, an explanation of the way they figure it wouldn't go amiss.

    The guess does seem to be decreasing every month, I'll see how long it takes to become more realistic.

    Fortunately I don't have gas to worry about.
    Last edited by retrotecchie; 02-01-23 at 18:56.
  • Johnh1995's Avatar
    Level 18
    The way that Eon work out the estimated usage is a real mystery. My first two months from 1st October on v14, I used relatively low amounts of gas as we were away a lot. The recommended monthly DD for both gas and electric was £110. In December, we used considerably more gas but the recommended DD jumped to over £240, based on one months higher usage. The online system did not allow me to even change the DD, apart from having to accept £241.50 per month. Knowing that this was a totally fictional amount, and also being £400 in credit, I had to send a WhatsApp message for E.on to increase the DD by £20. So disappointing and it does show that you have to be very careful in what goes on.
    Last edited by Johnh1995; 02-01-23 at 21:06.
  • Mailman's Avatar
    Level 56
    The way that Eon work out the estimated usage is a real mystery. My first two months from 1st October on v14, I used relatively low amounts of gas as we were away a lot. The recommended monthly DD for both gas and electric was £110. In December, we used considerably more gas but the recommended DD jumped to over £240, based on one months higher usage. The online system did not allow me to even change the DD, apart from having to accept £241.50 per month. Knowing that this was a totally fictional amount, and also being £400 in credit, I had to send a WhatsApp message for E.on to increase the DD by £20. So disappointing and it does show that you have to be very careful in what goes on.

    What you describe is one of the reasons I elected to go Variable Direct Debit - at least I don't have to think about what Eon Next or anyone thinks is my 'estimated annual usage'. I'm much more focused on what my targets are - so for this January I looked at what I used for last year (1323 kWh Gas, 257kWh Elec) and set myself targets of 1147 kWh Gas/ 248 kWh Elec averaging 37kWh/day and 8kWh/day respectively. Doable for my house so long as the weather is no worse than it was in December.
  • retrotecchie's Avatar
    Level 92
    @Mailman

    I wasn't actually given a choice. For whatever reason, they stuck me on Variable from the get go. When I enquired into fixed DD, they wanted nearly £150 a month more than my variable usage worked out at. No way was I falling for that. Now when my old supplier paid 3% interest on credit balances when my bank was offering 0.2%...entirely different story!
  • Johnh1995's Avatar
    Level 18
    @retrotecchie
    Just curious which supplier offered a 3% interest on credit balances and do they still do it. I could be earning money back on my current credit balance if Eon Next offered that
  • retrotecchie's Avatar
    Level 92
    @Johnh1995

    Both my previous suppliers offered 3% on credit balances. My last supplier, Igloo, gave me 3% up until they went bust last year and were taken over by E.On Next. Most months I'd make a couple of quid. Prior to that I was with OVO but they don't serve most of Wales.

    I was one of OVO's first customers and earned £50 a pop for signing up new customers and the 3% interest on a credit balance of about £2000. In 2010 and 2011 the net flow of money was actually in my direction as I signed up about 20 friends, only really used gas (as I generated most of my own electricity) and they didn't have standing charges back then.

    Those days, unfortunately, are long gone.