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The calorific value is needed by the Smart Meter to convert the volume of the gas to the energy produced by the gas Kwh. As this varies on a daily basis what value does the meter use?



Is this the same value as used by the bill?

Updated on 05/12/24 by Emmanuelle_OVO:

 

Great question to ask. You may have noticed your smart meter will show your gas readings in both volume (metres cubed or m3) and in the kWh units that are charged on your monthly summary.

 

In order to covert a m3 unit to kWh, we need to carry out a complex equation which involves taking into account the calorific value of gas. As this can change month to month, the calorific value we use to calculate your charges may differ slightly to the one used by your meter, which uses a set value of 39.2. As the calorific value changes so often, it's not practical for the meter to be constantly updated with it. However your monthly summary will use the up-to date calorific value that you can find online here.

 

When submitting your meter readings manually on your online account or OVO app (download for Android or iOS), you’ll only need to send us the m3 figure and we’ll do the rest. Find out how to read your meter reading manually here.

 

Hope this helps :slight_smile:


Anyone want to take a stab at this? Bear in mind I don't have a smart meter so the readings are actual. 

As an example of one statement. On checking my last statement re my meter readings my recorded gas usage was 67 ft3.

 

Converted to cubic metres is 189.7229

 

Converted to kWh is 2122.3869

 

Ovo charged me for 2138 kwh

 

 

 


Hey @NoiseMaker,

 

You’ll need to convert the volume you used to the energy value, you’ll need your calorific value to do this. Check the best answer for info on where to find this. 

 

Here’s the calculation for Imperial meters:

(Number of gas units used) x 1.02264 (Volume correction, which takes into account changes such as temperature and pressure) x 39.42 (an average Calorific value) / 3.6 (conversion to Kwh) x 2.83 (adjustment for imperial units) = Usage in Kwh
 

Here’s the calculation for Metric meters: 

(Number of gas units used) x 1.02264 (Volume correction, which takes into account changes such as temperature and pressure) x 39.42 (an average Calorific value) / 3.6 (conversion to Kwh) = Usage in Kwh

 


Hey @NoiseMaker,

 

You’ll need to convert the volume you used to the energy value, you’ll need your calorific value to do this. Check the best answer for info on where to find this. 

 

Here’s the calculation for Imperial meters:

(Number of gas units used) x 1.02264 (Volume correction, which takes into account changes such as temperature and pressure) x 39.42 (an average Calorific value) / 3.6 (conversion to Kwh) x 2.83 (adjustment for imperial units) = Usage in Kwh
 

Here’s the calculation for Metric meters: 

(Number of gas units used) x 1.02264 (Volume correction, which takes into account changes such as temperature and pressure) x 39.42 (an average Calorific value) / 3.6 (conversion to Kwh) = Usage in Kwh

 

Yes. I've seen this. So please go ahead and apply that to my meter reading above and tell me your answer at each stage. Don't forget,  you're using the 67 ft3 to start.


We really need to see the calorific value used on your statement, @NoiseMaker, if you need this looking  into as it is account specific, please reach out to the team. 

You can send us a message on Facebook, Twitter, webchat via the Help Centre. You can reach our team on: 0330 303 5063. Our opening hours are 8am-6pm Monday to Friday.

Thanks!


Hi @NoiseMaker. I gave quite a full answer to this very issue over here on another Topic last year.


Hi Everybody

 

I’m trying to figure out roughly how much per hour it costs me to have my heating on.

 

I swithched my heating on for 1 hour and did readings just before and just after.  I used 0.765 m3.  How on earth do I tell how much that is in kWh so I can tell roughly how much per hour my heating costs?  I know it can vary due to temp of gas …etc etc , but I just want a ball park figure?

 


I make it 88p but prepared to be corrected !!

(assuming calorific value average figure of 39.2)

(vol x calval x 1.02264) / 3.6

assuming 10.3 p/kWh


Thanks!  The calculation is very complicated for me!  


I check my app nearly every day, checking my KWH (as opposed to cost). I figured the kwh don't change, I use what I use each day (I am on a smart meter).

I checked all through Dec and every say was between 11 and 13 kwh. HOWEVER, I go in on the day I am billed and every single day in Dec shows TWICE as many kwh used as when I was checking.

Question - why did my kwh change? I didn't suddenly use more kwh once I got my bill! Has this happened to anyone else? I am writing everything down this month and taking screwn shots as proof should OVO do that again!!!!


Hi @KayCommis have you checked your meter readings? If so are these actual or estimated? (They might still be estimated at some times even with a smart meter). This might be the reason. Otherwise, depending on your heating, it was much colder during that time so your heating probably use more


Hi @KayCommis have you checked your meter readings? If so are these actual or estimated? (They might still be estimated at some times even with a smart meter). This might be the reason. Otherwise, depending on your heating, it was much colder during that time so your heating probably use more

But the app tells me about 2 days later what I used on the day.... so for example, on the 13th of the month the app will tell me my exact daily use of 11th of the month. 

 

I thought smart readers meant that I don't need to send meter readings anymore?


Hi @KayCommis have you checked your meter readings? If so are these actual or estimated? 

 

I thought smart readers meant that I don't need to send meter readings anymore?

Generally yes but they can occasionally lose signal so it’s worth just checking what it says against your meter readings

https://account.ovoenergy.com/meter-readings


So here is my electricity meter reading page for example. If it is working perfectly you will see a reading every day with the word Smart next to it. 

 


My Liberty EG4v10 meter was installed in 2015. So an early one.
Can anyone tell me if the original readings were in cu ft or cu M?
Thanks.


Hey @carmelsdad26 ,

Sure thing! That meter - and all Smart Gas Meters - uses Metric measurements, so it’d be Cubic Metres. The last known install of an Imperial Gas Meter was something like 20+ years ago at this point which would have been long before Smart Meters were even being designed.

Hope this helps!


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