[Andy65]

Originally Posted by Mac9091

You say it may only be pennies but they all add up.

Just think if eon "mistakenly" took an extra penny from every customer in every direct debit...that's a lot of free money at the end of the year.

And how many people would complain about a few pence, let alone even notice it?

Insignificant and pointless I would have thought, especially when they just add a tenth or two of a penny to the cost of 1 kWh and they'll be reaping it in every hour of the day and night.

[houghtonj957]

@JimL I have exactly the same error in basic arithmetic on around 20% of my bills. The rest of this thread seems to miss the point. I've raised it with E.ON Next and they tell me that their system is automated and not prone to errors.They also say this issue has not been raised before. I don't think it results in incorrect amounts being billed. It just makes it impossible to verify the amount being billed. Nothing to do with rounding, smart meters and all the other things mentioned. It's a simple error in arithmetic that a 10 year old could correct.

[JimL]

@houghtonj957 That statement " system is automated and not prone to errors.They also say this issue has not been raised before" raises 2 questions in my mind
1. The incorrect result of the equation clearly shows an error - so the 1st statement is fatuous.
2. I raised this issue when I started this thread. I also raised it again last week (5/8/24) as a complaint because EON fabricated a previous meter reading (plucked out of thin air) AND got the calculation wrong (again) to boot. So the 2nd statement is a blatant LIE! If you speak to them again about this and they tell you "it's never been raised before" ask them to check complaint ref - 1571464.
Also, the equation error DOES result in incorrect amounts being billed. 2p in my case. Irrelevant you say. The advisor told me EON have 3 million customers. That amounts to £60,000 per month at 2p per customer

[meldrewreborn]

I suspect that if they use a rounded reading one month any inaccuracy will be countered the next or later subsequent months. All the factors in the calculation are static, apart from the readings and the calorific value. If the readings can’t cause any repeated error that only leaves the calorific vale. Now this does drift as the mix of gas gradually changes over time but probably individually computed to each account as the reading dates will differ, although smart meter reads will be more standardised.
I, and many others, are not sleeping too well at the moment, but in future I may return to thinking about this topic as it will likely send me off quite quickly, despite the heat.

[Mailman]

@houghtonj957 @JimL

The figures are correct for my kWh gas consumption as can be seen over the last 7 months on attached picture. Gas smart meter reads are recorded by myself accurately (to 3 decimal places) just before midnight on the day the reads are pulled on schedule. The bills themselves do not show this degree of precision although I suspect that 'rounding' is only done when the final kWh figure is produced and the accounts themselves only show integer values. Even so my billed kWh usage over the last 7 months have matched very very closely with the kWh that I have calculated. The very slight variance is undoubtedly due to the CV being shown to only 1 decimal place on our bills although I suspect that a higher degree of precision is used. Unless you carry out the same degree of precision that I have sadly done 😉, there will be ups and downs each month on your kWh calculations.

[JimL]

@Mailman I think this thread is veering off and muddying the waters from my original complaint/point. Just to clarify (roundings etc have no relevance to any of this) the following equation is a 'cut and paste' from my previous bill
Gas charges for meter *************
15 Jul 2024 883.0 Smart meter reading
1 Aug 2024 884.0 Customer reading
Consumption 1.0 Units (m3)

Yep, I am a REALLY low user.

Unit consumed (cubic metres)
× Volume correction (for temperature & pressure)
× Calorific value (energy in each m3 of gas)
÷ 3.6 (convert from joules)
For you:
1.0 × 1.02264 × 39.7† ÷ 3.6 = 11.8
(The equation - left of the = sign) has no roundings for cubic meters (1.0) and the only variant is the "†Average calorific value shown to one decimal place" - 39.7 in this instance

Now, using a calculator 1.0 × 1.02264 × 39.7† ÷ 3.6 = 11.27745 (or 11.28/11.3 to 1 dec place) NOT 11.8
Simple primary school maths and Eon are getting it wrong
PS - In order to arrive at a result of 11.8, the average calorific value would have to be 41.6 - can't round up 39.7 to 41.6

[Mailman]

Originally Posted by JimL

@Mailman I think this thread is veering off and muddying the waters from my original complaint/point. Just to clarify (roundings etc have no relevance to any of this) the following equation is a 'cut and paste' from my previous bill

We shall have to agree to differ about the roundings issue.

From what I can see from your workings, you are assuming (not unreasonably) that the 'system' is calculating all kWh usage using the meter reads as displayed in your bill (to 1 dp). I am suggesting that the 'system' actually uses the raw meter reads (correct to 3 dp) between meter advances in the calculations. Indeed it was only doing this that I managed to reconcile monthly kWh usage (and hence £ gas billing) to within 1p.

From my perspective the numbers used on each bill display meter reads rounded to 1 decimal place. As you can see from my worked examples stretching back this year, when I used the actual meter reads to 3 decimal places you get gas kWh in agreement with what is shown on my bills. I'm not sure about the precision of the CV used in the calculation as to whether your bill displays the rounded (or truncated?) value to 1 decimal place but uses more precision in the calculation. What I do know is that when I round off at the end of the calculation the biggest error between my own bills (calculated using precise meter reads to 3 decimal places) and Eon Next bills (showing 1 dp only) is 0.15 kWh which equates to approximately 0.9p! The average difference over my 7 months was only 0.005 kWh i.e 0.03p

To give you an example from my latest bill:

Unit consumed (cubic metres)
× Volume correction (for temperature & pressure)
× Calorific value (energy in each m3 of gas)
÷ 3.6 (convert from joules)
For you:
8.3 × 1.02264 × 39.8† ÷ 3.6 = 93.3 kWh ONLY

when you do the calculation as it stands you get 93.8385 rounded to 93.8 kWh (not the 93.3kWh that you see on the bill)

so it looks like I have been cheated by 0.5kWh (approx 3p). Now go back to the table in my previous post where you see that the actual meter difference was 8.255 M3. Now lets see what happens when you use this instead 8.255 X 1.02264 X 39.8 ÷ 3.6 comes to 93.329 which now agrees with what you see in my table in previous post (93.330 kWh) and the result in the above calculation shown on my bill (93.3kWh).

I am confidant that Eon Next are not cheating you or anyone else although it does boil down to bill presentation and the assumptions made in the numbers presented. I am also confidant that Eon Next's back end uses unrounded/untruncated data in the actual kWh calculation but displays a limited display rounding. 👍