How can I work out my gas costs from my meter readings?

  • 26 February 2018
  • 9 replies

Hello fellow OVO’s!

Would someone workout for me how much my gas as cost me over a 24 hour period?

The gas meter reading was 18243 after 24 hours it read 18248, therefore I used 5 kWh for that period.

The price of the gas is 2.55 p/kWh, I'm little confused on how to work it out for myself.

I thank you in advance for answering my question.

"I'm not very clever, but I'm good at lifting weights" 😟


Best answer by Transparent 1 March 2018, 15:31

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9 replies

Userlevel 7
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Hi @Robotrobo,

Well I can't see your Gas Meter, but I'd suggest that it's reading cubic-feet or cubic-meters rather than KWh

Also I can't fully answer your question because I don't know if you also have a Standing Charge to take into account.

To find this out, log in to your account by choosing either
Pay Monthly (Direct Debit) customers
or Pay As You Go customers

then click on My Profile from the menu on the left.
The costs of your units are given in the second section "My Plan", which you'll have to scroll down to view. That will tell you if there's an element of Standing Charge.

Returning to the Meter reading itself, your OVO Statements have a page "Explaining your Gas Statement" which shows the calculations they do to convert Cu.Ft or Cu.M to KWh. The line reading Volume conversion factor will tell me what units your gas meter is measuring.

Have a look at that first.

If it still doesn't make sense, ask a more specific question and I'll try to help some more.
Hi transparent.
My meter is a metric cubic meters and the standing charge is 27.40p per day, as I say I used 5 units of gas in a 24 hour period,
I have recently fitted a new gas fire & I am trying to work out how much it is useing over a short period, l hope I am making it easier for you to work out for me.
Userlevel 7
Badge +5

Updated on 14/07/21 by Jess_OVO:

Great question to ask about the conversion of your gas meter readings (which track your usage in volume  - ie. metres cubed or m3) to your energy charges (which are based on the cost per kWh of gas used).

It’s worth mentioning that if you’ve got a smart meter installed you don’t need to work this one out manually - you can check your daily usage costs is on the usage pages of your online account or OVO app (download for Android or iOS).  

If you’re yet to get a smart meter installed or want to do the calculations yourself, check Transparent’s advice below:


Thanks @Robotrobo,

I'm going to show my workings -
not just so that others can follow it if they find this thread in the future, but because I want a good grade and a gold-star! 🆒

  1. You've used 5 cubic metres. There's no volume conversion factor to take into account, because it's a metric meter. If the reading was in cubic feet, then we'd have to multiply by 2.83
  2. Apply a volume correction of 1.02264 to allow for changes in temperature and pressure. This figure is approved by Ofgem. 5 x 1.02264 = 5.1132
  3. Multiply by the calorific value. Domestic gas is a mixture of butane, propane and others, which give off different quantities of heat. This mix varies during the year depending on where the UK gets its gas. Currently the calorific value is 39.1 So 5.1132 x 39.1 = 199.92612
  4. Convert from Joules to kilowatt/hours, dividing by 3.6; 199.92612 / 3.6 = 55.535 KWh
  5. Cost at 2.55p each, 55.535 x 2.55/100 = £1.4161
  6. Add the day's standing charge of 27.4p; £1.4161 + 0.274 = £1.69
  7. Plus 5% VAT comes to £1.77

Now, this isn't particularly accurate because I'm pretty sure that the meter didn't exactly pass through 5 cubic-metres. It might have been 4.65 or 5.37 or whatever.

But you wanted to have estimate over a short period, so that's what I've calculated.


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Userlevel 6
Gold star indeed @Transparent :D

@Robotrobo if you need to find your calorific value, it's on page 5 of your statement. This will vary from region to region and month to month, depending on the mix/quality of the gas purchased.

Let me know if you have any further questions!


Hi there,


I had both my electricity and gas meters changed in September this year(by an OVO engineer on behalf of Spark Energy), however, because the gas meter is way too far from the electricity one, the gas one is not sending the required data in order for my supplier to update my bills and bill me correctly. So for the last few months I have been paying the estimates which go higher and higher each month.


The problem that I find right now which scares me the most is that on the gas meter display, it shows the reading of 250(m3). This is from the start of september until now, the end of December. I checked the pictures of the old meter and that one had something like 7800(an old meter) but not completly sure in what mesuring unit. I suspect something such as foot cubed/cubic feet.


What scares me is that if the reading with 250m3 goes through, wont I be charged an outrages bill? Based on online conversions, 250m3 would be equal to 8828 cubic feet. That is more than the old meter had since it was installed. There is no way we used 250m3 in 4months. We have a 2 bed apartment, not a steel mill running 24/7.


Can someone explain to me if I am overexagerating here or if I did my calculations wrong.



A dumb meter

Userlevel 7

Good question, @Dumb-meter - have a look at the ‘best answer’ at the top of this topic!


Any questions, @Transparent will be able to help you out! :blush:

Userlevel 7
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Panic not, @Dumb-meter. 250m³ is just over 700 cubic feet.

But you’re right to be checking this...

During 2020 we should be seeing greater variations in the calorific value of gas supplied to our homes. This will be due to increasingly more hydrogen and methane being added from renewable sources within the UK.

Since these gases yield less heat, the calorific value will be slightly lower in some regions of the UK. That’s fine because the National Gas Network has 53 sampling points which are checked daily. This will be reflected in your OVO bills.

But it means that you will see a correspondingly higher volume of gas passing through your meter, which may cause alarm to some people who compare usage only by recording the raw figure from the meter itself.

I expect we’ll need to discuss this further here on the Forum during the next few months.

Thank you for the help @Transparent and @Tim_OVO 

Based on the calculations above, we used less compared to the estimates from Spark(my provider) so I can relax until then.


I have another question regarding the meters, but this is not about the volume but mostly on how the system works.

Because my gas meter is too far away from the electricity meter, my readings are not being sent to the collection servers and so my account from my provider is not being updated properly. I have asked them to supply me with a relay (something that OVO provides to their customers, and because Spark is owned by OVO, I was hoping to be able to get one as well).

The response that I got from Spark Energy support team was that even if I got a relay (they did not even bother to proceed with my request), they would still have to wait for the national database to be updated with my new meter before I would be able to use it.


My confusion here is that during the installation of both meters, the engineer installed and then took off again the new gas meter just to physically take it close to the electric meter (which was installed first and was running at that point) in order to pair them.

If I was to get a relay and have the gas meter finally connected to my electricity meter, wouldn't the readings sent by the meter notify the collection server that the meter is active and force the database to update?

Or do I have to get an engineer back to my location with a relay and have him connect the meters again and notify the system that the meter is active?

I checked the meter details and in one of the “Identification” panels, the “site ID” is blank but it does have an “Installation ID”, a“MAC” address and a “Meter number”.

Userlevel 7
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Your observations are excellent @Dumb-meter .

I also noted that there were problems with the commissioning sequence on my first set of SMETS2 meters, and wrote about it here on another Topic. This feedback was taken on board by OVO and the installations on both of my subsequent two visits were undertaken in a different order.


Turning to the matter of Zigbee Repeaters, these have been deployed by several Energy Suppliers (incl OVO) for their own proprietary installations of SMETS1 meters.

However, Repeaters are not an approved part of SMETS2 installations.

I did at one stage buy one and tried getting better signal strength between my gas meter and the Comms Hub. You can read about those tests here.

The issue was eventually resolved by one of OVO’s SMETS2 Engineers downloading fresh software to my site. So that suggests a Repeater is not the answer.


Overall I still think there are deficiencies in the specification for SMETS2 Gas Meters.

  • They should have an alternative radio communications link operating at 868MHz which has better penetration of solid objects.
  • They should have a “commissioning mode” whereby they send data to the Comms Hub every 30 secs instead of 30 minutes. That would enable the Installers to confirm operability whilst still on-site.

I have fed both of these points back to Ofgem as part of their public consultation on Smart Meters which was completed in Autumn 2019.


Now that OVO has been permitted to acquire the retail sales division of SSE and become the third largest UK Energy Supplier, I hope they will make good use of the extra clout to seek enhancements to the SMETS2 technology which will reduce on-site faults.

I’m just tagging @BenS_OVO here to make sure he reads this Topic. But I don’t think any of this is new to him, so don’t expect him to respond on the open Forum.