Octopus Watch - conversion from m3 to kWh

PennineAcute

Does anyone know how accurate OW are with the calorific value?  Do they use the truncated to 1dp value available on the web, or do they use the true value?

I ask as I notice there is a difference between their daily gas usage readings and my IHD.  Sometimes 1 kWh difference.  EG Sunday, which is the latest OW reading for my gas, they have calculated I have used 8.59 kWh of gas.  My IHD says 9.13 kWh.

[Deleted User]

PennineAcute said:

Does anyone know how accurate OW are with the calorific value?  Do they use the truncated to 1dp value available on the web, or do they use the true value?

I ask as I notice there is a difference between their daily gas usage readings and my IHD.  Sometimes 1 kWh difference.  EG Sunday, which is the latest OW reading for my gas, they have calculated I have used 8.59 kWh of gas.  My IHD says 9.13 kWh.

The gas proxy meter in the comms hub uses a fixed calorific value which is why usage on bills is different from what is shown on IHDs.

PennineAcute

[Deleted User] said:

PennineAcute said:

Does anyone know how accurate OW are with the calorific value?  Do they use the truncated to 1dp value available on the web, or do they use the true value?

I ask as I notice there is a difference between their daily gas usage readings and my IHD.  Sometimes 1 kWh difference.  EG Sunday, which is the latest OW reading for my gas, they have calculated I have used 8.59 kWh of gas.  My IHD says 9.13 kWh.

The gas proxy meter in the comms hub uses a fixed calorific value which is why usage on bills is different from what is shown on IHDs.

So OW is accurate, would you say?

[Deleted User]

PennineAcute said:

[Deleted User] said:

PennineAcute said:

Does anyone know how accurate OW are with the calorific value?  Do they use the truncated to 1dp value available on the web, or do they use the true value?

I ask as I notice there is a difference between their daily gas usage readings and my IHD.  Sometimes 1 kWh difference.  EG Sunday, which is the latest OW reading for my gas, they have calculated I have used 8.59 kWh of gas.  My IHD says 9.13 kWh.

The gas proxy meter in the comms hub uses a fixed calorific value which is why usage on bills is different from what is shown on IHDs.

So OW is accurate, would you say?

OW should be accurate as it gets its information from your Octopus account via API not from your smart meters.

That said, bear in mind that what you see in the Octopus App is 30 minutes short of a day. That is why, if your billing date is the 27th, you don’t get a statement until the 29th. Octopus needs to get the data for the 28th to recover the missing 30 minutes.

matelodave

There's a better than even chance that the IHD data has a fixed calorific value that was set when the equipment was installed and so only gives a rough idea of the cu.m-kwh conversion (Eon reckon +/- 5%)

The data that suppliers used will be derived from the readings that the meter sends (in cubic metres, not kwh) to the DCC and should be using the CV for the period of the bill, so its quite likely that the IHD info is different if it doesn't update with the current CV.

Netexporter

Similar to Agile having only a fixed value set for the IHD, rather than it tracking the half-hourly rates. The bills are correct at the end of the month, which is what really matters.

PennineAcute

Netexporter said:

Similar to Agile having only a fixed value set for the IHD, rather than it tracking the half-hourly rates. The bills are correct at the end of the month, which is what really matters.

My reasons for asking was for my spreadsheet and not for thinking my billing was wrong.

I use (or now used) my IHD to track my gas usage on my spreadsheet.  This calculates my average daily usage.  My spreadsheet accounts for difference between IHD usage and actual usage (and therefore cost) when I enter the latest billing info.

I did toy with using the calorific values from National Gas, but as these are truncated to 1dp, the calculated kWh would still have been inaccurate.  Now I know that OW kWh are accurate, I can now use these figures when entering my daily usage.  Keeps my data and forecasts more accurate.

[Deleted User]

PennineAcute said:

Netexporter said:

Similar to Agile having only a fixed value set for the IHD, rather than it tracking the half-hourly rates. The bills are correct at the end of the month, which is what really matters.

My reasons for asking was for my spreadsheet and not for thinking my billing was wrong.

I use (or now used) my IHD to track my gas usage on my spreadsheet.  This calculates my average daily usage.  My spreadsheet accounts for difference between IHD usage and actual usage (and therefore cost) when I enter the latest billing info.

I did toy with using the calorific values from National Gas, but as these are truncated to 1dp, the calculated kWh would still have been inaccurate.  Now I know that OW kWh are accurate, I can now use these figures when entering my daily usage.  Keeps my data and forecasts more accurate.

I admire your diligence but with so many third-party apps that use actual API account data to come up costs, my spreadsheets have largely become redundant.

PennineAcute

Dolor said:

PennineAcute said:

Netexporter said:

Similar to Agile having only a fixed value set for the IHD, rather than it tracking the half-hourly rates. The bills are correct at the end of the month, which is what really matters.

My reasons for asking was for my spreadsheet and not for thinking my billing was wrong.

I use (or now used) my IHD to track my gas usage on my spreadsheet.  This calculates my average daily usage.  My spreadsheet accounts for difference between IHD usage and actual usage (and therefore cost) when I enter the latest billing info.

I did toy with using the calorific values from National Gas, but as these are truncated to 1dp, the calculated kWh would still have been inaccurate.  Now I know that OW kWh are accurate, I can now use these figures when entering my daily usage.  Keeps my data and forecasts more accurate.

I admire your diligence but with so many third-party apps that use actual API account data to come up costs, my spreadsheets have largely become redundant.

One of the main reasons why I wrote it (a few years ago) was that I needed to brush up on my spreadsheet skills for work and teaching.

I joined OW to see if my calculations for Agile (when I was on Agile) were working, as these were a bit more complicated than Tracker, which I am on now. 

My spreadsheet does more than some the apps I have seen.  For example, I know that if my median Tracker rate  rises to 30.85p by 16 August next year, my forecast of £253.68 end of tariff will be wiped out and that my DD of £95.45 will leave me with a zero balance.  Even if the worse case scenario happens, I will still be quids in.  My current balance does include £100 referrals and a £30 goodwill gesture when they messed up.

I have also looked at some of the apps and incorporated things I like into my spreadsheet.  Some took me a bit to get working, but I got a big sense of satisfaction when they did work.  Why pay for an app when I can do it myself, and use that self-taught knowledge for work.