Real time gas data in m3

Cirrus1

Hi,
Is there an app to this? I don’t want the conversion done for me.

I thought Bright would do, but there is no option to see m3, only kWh. I would be happy with the latter had it been accurate. When I convert the end of day Octopus value (m3 to kWh using the Octopus formula) it does not match the Bright end of day value. There is at least a 4% discrepancy.
Octopus told me that their home display was not compatible with my EV tariff and never showed gas data,  so I no longer have it.

[Deleted User]

Hi,

Cirrus1 said:

Hi, When I convert the end of day Octopus value (m3 to kWh using the Octopus formula) it does not match the Bright end of day value. There is at least a 4% discrepancy.

are you getting the exact end of day meter reading, using same conversion factor?

[Deleted User]

Cirrus1 said:

Hi,
Is there an app to this? I don’t want the conversion done for me.

I thought Bright would do, but there is no option to see m3, only kWh. I would be happy with the latter had it been accurate. When I convert the end of day Octopus value (m3 to kWh using the Octopus formula) it does not match the Bright end of day value. There is at least a 4% discrepancy.
Octopus told me that their home display was not compatible with my EV tariff and never showed gas data,  so I no longer have it.

No. I assume that we are talking smart meters. The gas meter only sends a usage figure (in kWh) to the gas proxy meter in the comms hub every 30 minutes (to protect battery life). Bright pulls gas usage data from the gas proxy meter as does your supplier. 

There was/is an issue with block start and finish times. I believe that Octopus uses the block end time for each 3” minute period 2330 and it picks up the 2330 to 0000 usage on the data pull 24 hours later. Bright uses the block start time.

I am on Octopus Go and my Chameleon IHD6 shows electricity in kW and kWh, and gas in kWh.

All volume to kWh conversions are technically wrong (including the Octopus App) as they use a fixed calorific value whereas actual billing is on an average calorific value.

glennevis

Quote

"All volume to kWh conversions are technically wrong (including the Octopus App) as they use a fixed calorific value whereas actual billing is on an average calorific value."

And just to complicate matters further, as well as the timing errors @[Deleted User] notes, there are rounding (truncation) errors in most calculations due to the number of decimal places used by Octopus and Bright vs the 3 decimal places recorded on the smart gas meter (my experience).

My gas company claimed I had used 0 kWh gas on my first bill a month after gas smart meter installation. In fact the meter read 0.996 m3 units which is ~11 kWh but was truncated to 0.

By the way, I've tried 4 android apps and none show m3 gas usage. I don't know if the DCC database even allows these third party data handlers access to that data.

Even worse, one of the apps didn't allow you to view kWh for either gas or electric. That's taking dumbing down to a whole new level. My app of choice is Bright as their screenshots are free from gimmicks, nice and simple.

Cirrus1

Dolor - Thanks. However, I can see 30 min interval data in m3 for yesterday’s usage. I see this on Octopus and OctoWatchdog. Therefore, the meter must have sent the readings in m3. It maybe that the meter uses some algorithm and converts the m3 to kWh and sends this as well, but I can’t imagine why it would do so. It would be extra processing and more data sending, completely unnecessary.

When Octopus generate my gas bill it is based on two m3 readings and a formula applied to the difference.
I am just wanting to see real time gas data in cubic meters - not a lot to ask for. Maybe will have to make do with looking at one day’s old data at best.

[Deleted User]

Hi,

Cirrus1 said:

Hi, When I convert the end of day Octopus value (m3 to kWh using the Octopus formula) it does not match the Bright end of day value. There is at least a 4% discrepancy.

what is the 4% discrepancy in monetary terms, please?

[Deleted User]

Cirrus1 said:

Dolor - Thanks. However, I can see 30 min interval data in m3 for yesterday’s usage. I see this on Octopus and OctoWatchdog. Therefore, the meter must have sent the readings in m3. It maybe that the meter uses some algorithm and converts the m3 to kWh and sends this as well, but I can’t imagine why it would do so. It would be extra processing and more data sending, completely unnecessary.

When Octopus generate my gas bill it is based on two m3 readings and a formula applied to the difference.
I am just wanting to see real time gas data in cubic meters - not a lot to ask for. Maybe will have to make do with looking at one day’s old data at best.

Real-time volume data is meaningless to most people: hence the kWh conversion. People are also billed for kWh.

The algorithm as you put it is a simple M3 to kWh conversion based on a fixed calorific value. 

If you look at the calculation on your latest statement then kWh/M3 gives you the conversion factor of 11.xx for the CV used.

NannaH

Yep.
I’ve used 4 gas units today on my m3 meter , so 4 x 11.187 = 44.748kwh = £4.63. 

Cirrus1

frugal - the difference can be anything from 10kWh to 3kWh per day, Bright has the higher value every day. It soon adds up over a month.
Dolor - I have no idea how useful or not real time volume data is to most people. I was not pondering over this, but was asking a specific question. To conclude I think no app is available.

I am fully aware of being billed in kWh and have setup a spreadsheet. The formula is given in every bill and the maths is not difficult.
Since I am billed on the Octopus values for volume (then converted to kWh), if an app shows me inaccurate kWh data, it is if no use to me. I will stick with the day old volume data that Octopus provides.  At least my daily kWh calculation will be correct and the summation over the month should agree with the bill. I did this with November’s data and I came out with the same integer value for cost. I wasn’t expecting the decimal to be identical because of rounding errors and was off by 20p.
This isn’t a little exercise of mine to pass the time of day. The cost of gas is such and our usage high, that I want to know of what sort of bill to expect. Accurate data achieves that.

[Deleted User]

Cirrus1 said:

Since I am billed on the Octopus values for volume (then converted to kWh), if an app shows me inaccurate kWh data, it is if no use to me. I will stick with the day old volume data that Octopus provides.  At least my daily kWh calculation will be correct and the summation over the month should agree with the bill. 

Edit:

After looking through all the third-party apps, it would seem that Octo-Aid might give you the information that you are seeking. It uses your account API key to retrieve data from your Octopus account as opposed to pulling data from your smart meter. You set the caloric value.

 

Cirrus1

Dolor - many thanks for the suggestion. I downloaded the Octo-Aid app. I can not get it to accept my data. One section wants API key and account number. I have tried copy and paste, writing in the values manually, but all to no avail. I know where to get the data it wants. It just will not accept any MPAN, MPRN, serial number etc and I know that I am not making mistakes. I have fed other Octopus apps the same information successfully (OctoWatchdog). Shame, it would have been nice.