Conversion of M3 to Kwh (as opposed to Khw!)

MWT

If we assume the CV is correct then it points at the meter readings or consumption being rounded for display but calculated to a higher degree of precision...

My last bill would suggest that 29.77m3 was used in the calculation if the CV is correct, but the bill shows 29.8 units used with readings of 3414.1 and 3443.8 which would appear to be 29.7 used.

I'm betting that is the problem rather than the CV as otherwise there would be two errors in the calculation where it can be explained by just the one.

[Deleted User]

https://www.legislation.gov.uk/uksi/1996/439/made/data.pdf

This is the actual legislation that must be followed, but I have a feeling they don't describe how to get the m3 value that goes into the start of the calculation.

calorificvalue

With regard to the 5.6 / 5.7 difference

This is the first occurrence of an a - b error.

I am hoping that the next bill may create a -0.1 effect and thus self-correct.

But if it does not then the readings from the opening balance will not tally with the units used.
I cannot help thinking it may be +0.1 again which is obviously senseless.
The next bill is due beginning of OCTOBER. I will just have to wait and see.

But this is independent from the m3 to khw problem.

On the Business Energy website you will find a m3 to kwh calculator which will give results that you would normally expect.
It agrees with my calculations & with you guys, but not with OCTOPUS's weird results.

k_man

It looks like Octopus use m3 readings of more than 1 decimal place (as Smart meters give that level of accuracy), for their calculations of m3 used and then m3 to kWh.

But they only display to 1 decimal place on the bill.

[Deleted User]

k_man said:

It looks like Octopus use m3 readings of more than 1 decimal place (as Smart meters give that level of accuracy), for their calculations of m3 used and then m3 to kWh.

But they only display to 1 decimal place on the bill.

Yes, I'd agree with you and with MWT.  Much more likely to be a discrepancy in the m3 value rather than in the application of the standard calculation.

The_Green_Hornet

I agree with the OP. The calculation on the bill is clearly wrong and Octopus should correct it regardless of whether it a rounding error or that it should balance out over time.

k_man

I suspect the solution would be to show the decimal places used.
 The calculation used is likely correct, just displayed with inconsistent decimal places.

This may lead to more confusion, as meter reading are historically only to 1 DP for gas m3.

calorificvalue

The_Green_Hornet said:

I agree with the OP. The calculation on the bill is clearly wrong and Octopus should correct it regardless of whether it a rounding error or that it should balance out over time.

Thanks,

On the first occurrence I went to the trouble of creating a spreadsheet trying to ascertain all the possible values for the two variables (cal val & units used) to two decimal places within rounding up and down ranges to generate their end result.. It involved OVER 40,000 (FORTY THOUSAND) combinations. (or was it lines-a lot anyway). None of which matched, and the few that came the closest didn't really make sense. It needed readings of two decimal places.
I just need enough people to complain to make them tell the truth. Either it's a scam waiting tin the wings or they just incompetent. They are only a limited number of combinations possible given the scenario involved. 
All I want them to do is revert back to the pre May calculation which was perfectly acceptable.

MWT

k_man said:

I suspect the solution would be to show the decimal places used.

... or probably easier, just do the calculation using the same values as are displayed in the bill...

The real mistake though was to move away from just using whole numbers simply because they could...

[Deleted User]

calorificvalue said:

Either it's a scam waiting tin the wings or they just incompetent. 

That's where your problem really lies.  You decided that there's some deliberate scam to cheat customers out of money - hence the aggressive way you approached the issue when you started spamming the forum earlier.

Now we've had some actual details and discovered plausible explanations for it, you've added incompetent as an option.

Reality is probably more like the billing department have decided to 'upgrade' the calculations by taking advantage of the additional accuracy provided by smart meters and nobody has noticed the inadvertent issue this created with the narrative on the bills.  I wouldn't even stretch to call that incompetent, only unfortunate and disjointed.

Just remember, you already 'win' on every CV calculation if they are truncating rather than rounding the value used.