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When I check my Gas Bills, I am finding that, using the Calorific Value stated on page 6 of my Bill, the kWh used figure does not work out as per the value stated. This seems to be because the calculation was not made using the Calorific Value quoted. Usually it is only an error of plus or minus 0.1 of the stated value but it should be the correct value or else the bill is technically wrong !  

Why can you not get all of the figures correct so that the bill can be checked fully?

Updated on 03/01/25 by Emmanuelle_OVO:
 

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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:

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As I am new to OVO from SSE, I think I have fathomed out the workings of my first OVO bill. Only one thing that seems to missing from my OVO bill that was on my SSE bill is the calorific value used towards accurate calculation. All it says on the OVO bill is to view the National Grid site for these values. I do know the value fluctuates and that probably an average of the fluctuations is used the finalize the figures but to me the actual figure used should be shown on the bill to enable myself to accurately check OVO figures to the penny. If anyone is interested I could put the National Grid values for each calendar month on this site.


If anyone is interested I could put the National Grid values for each calendar month on this site.

Go for it! We love data here. :)


I think you are au fait with the OVO systems, so I will present the data at the end of the month if there is anyone out there that could use the values ;))


It looks like OVO along with every other gas supplier does/has to take the average CV of whatever period of days a bill applies to. So if trouble is taken to note CV value for each day of a period from National Grid is noted and and average taken, then the calculation is a simple one.

My remaining issue is why if SSE could show the CV used for the bill, why can’t OVO?

Calculation of average calorific value in accordance with the Gas (Calculation of Thermal Energy) Regulations 1996

Guidance on the calculation of thermal energy on the basis of determined calorific values

 Use of average daily figures Regulation 3 (2) states that the “average calorific value of gas so conveyed during any such period shall be calculated by adding the daily values…for each gas day in that gas period and dividing by the sum of the number of those gas days…”. National Grid is responsible for determining the daily average CV for each charging area. National Grid publishes this daily average CV for each charging area rounded to one decimal place in accordance with Regulation 4 (4) (set out in Appendix 1). National Grid then transmits this daily calorific value electronically to gas transporters and gas suppliers for their respective uses.


Further to previous comments about calorific value anomalies, I was interested in finding out what the variation in cost might be over a year given the criteria OVO have given on my bill:-

“The calorific value of gas changes every day and can range from 37.5 to 43.0”

The following table is based on using 1060 units of gas for 12months using CV from 37.5 to 43.0.

1060 units @ CV 37.5 = 11291.650 kWh = £1269.41

1060 units @ CV 38.0 = 11442.205 kWh = £1284.94

1060 units @ CV 38.5 = 11592.610 kWh = £1300.48

1060 units @ CV 39.0 = 11743.346 kWh = £1316.02

1060 units @ CV 39.5 = 11893.871 kWh = £1332.66

1060 units @ CV 40.0 = 12044.427 kWh = £1347.10

1060 units @ CV 40.5 = 12194.982 kWh = £1362.64

1060 units @ CV 41.0 = 12345.537 kWh = £1378.18

1060 units @ CV 41.5 = 12496.093 kWh = £1393.72

1060 units @ CV 42.0 = 12646.648 kWh = £1409.26

1060 units @ CV 42.5 = 12797.203 kWh = £1424.80

1060 units @ CV 43.0 = 12947.759 kWh = £1440.34

Without knowing the actual CV used by OVO, the average of the range above is 40.25.

Note that if the lowest CV is used (37.5) then any CV used between to a maximum of (43.0, then There could be a maximum overcharge up to £170. It could also be that an undercharge is possible but without OVO actually stating on each bill the actual CV used then each customer will have to resort to asking OVO which particular CV the have used to calculate a particular bill. I would appreciate a response from someone from OVO as this issue has been on the agenda for at least two years.


Hey @JGANLEY,

 

Thanks for a great conversation, 

 

The calorific value changes every day, so it’s not appropriate to put it on every single statement as there would be 30 odd values. The information comes from the National Grid.

 

It may be possible, if you contact Support for them to raise this to a specialist team to find out the values for a month statement. 

 

You might also be able to find out the calorific values from the National Grid.

 

Hope this helps. 


Thanks Emmanuelle_OVO.

I do know how to obtain daily CV from National Grid and also calculate daily and monthly averages. My questions are...why is the monthly CV not on my bill? As OVO must use a CV to help calculate the bill, then why do they not tell us this figure? SSE used to put the CV on the bill. I am sorry but to say it is not appropriate to put it on the bill is not satisfactory. It's like buying something for a shop and being told to work out the VAT yourself. I feel OVO are obligated to give all required data to enable customers to check the bill themselves. Afterall the CV average only needs entering once a month on the bill. I would be pleased for someone from OVO to publish the CV used for January. As a further point, I have raised this point with my MP and the requirement is being looked into. I do not want upset the apple cart. I just want to calculate my bill accurately myself. I am at present using the daily figures released by National Grid and have created a spread sheet which from readings and daily CV figures automatically gives exact costs but that is me doing it daily and if I can do it daily then OVO should at least be able to, once a month plus tell me how they have used the CV data, daily or averaged out over a month. Sorry, long winded I know but it is information that should be ailable OVO customers.

Regards


As I think I’ve commented elsewhere @JGANLEY I'm still not sure that an average figure is that simple. After all, it will not be just an average of each daily reading but an average at the various m3 conversion factors based on each daily reading. I realise this can be done but it looks more complex on that basis


I agree it may be complicated but my point is that it is not complicated for OVO and they should show all the data as was the case with SSE.


Yes I understand (and mostly agree) but even with an ‘average’ cv point, how on earth would an average user check this


You are correct BPLightlog. That is part of the point I am making. It should not be necessary for the average customer to check but if one does it is required that all the data is provided by OVO. One thing I forgot to mention is my calculations are base on metric meter readings, so metric conversion not required. Surely as as company, OVO can release the CV value used to finalize a bill. Computer systems are no longer steam driven;-))

I have now developed a spread sheet where daily readings are entered together with daily National Grid CV reading and automatic rolling average of CV calculated. Also all following criteria are auto entered:-

Metered volume × metric conversion factor × daily 1 calorific value from National Grid × 1.02264 (volume correction) ÷ 3.6 = 2 kilowatt hours (kWh) used. This gives a daily finite cost and after 31days the average value of CV is the figure automatically used.

This gives me precise costs but until OVO supply the exact way they calculate/use average CV data then this is as accurate as possible for man on the street.

In hope that OVO respond with a positive answer.


For info Emmanuelle_OVO - BPLightlog 

The following legislation does show requirement on how energy companies deal with CV data:-

 

Calculation of average calorific value in accordance with the Gas (Calculation of Thermal Energy) Regulations 1996

The CV used for consumer billing should be an average of the daily average values received from National Grid for the billing period. The use of a fixed CV, which some suppliers refer to as an ‘industry standard’, is not consistent with the Regulations. Requirement to truncate Regulation 3 (2) is clear that when calculating CV “any amount of less than 0.1 megajoules per cubic metre shall be ignored.”

This means that for a given gas billing period, suppliers should truncate the average CV to one decimal place. Rounding average CV is not consistent with the Regulations, nor is calculating to more than one decimal place.

All I need is for OVO to confirm this on my bill.


For Blastoise186 it relevant to the issue

The following legislation does show requirement on how energy companies deal with CV data:-

 

Calculation of average calorific value in accordance with the Gas (Calculation of Thermal Energy) Regulations 1996

The CV used for consumer billing should be an average of the daily average values received from National Grid for the billing period. The use of a fixed CV, which some suppliers refer to as an ‘industry standard’, is not consistent with the Regulations. Requirement to truncate Regulation 3 (2) is clear that when calculating CV “any amount of less than 0.1 megajoules per cubic metre shall be ignored.”

This means that for a given gas billing period, suppliers should truncate the average CV to one decimal place. Rounding average CV is not consistent with the Regulations, nor is calculating to more than one decimal place.

All I need is for OVO to confirm this on my bill.

That’s it for now...my MP is interested by the ambiguity this causes and awaits OVO response


Thankyou Emmanuelle_OVO

You say I may contact support. Why should people have to contact support for details of how OVO have calculated my bill. It is incumbent on them to provide that information on the bill. I have contacted support to no avail.

Below screenshot excerpt of SSE bill with calorific value shown. It was shown on every bill.

I will also point out that you must be aware that OVO did use to show the calorific value on the bill, then stopped doing so. Could someone answer why?

To verify OVO did used to show CV on their bills, I have attached a screenshot of an old OVO bill.

 


I’ve just looked through my old bills and all up to June 2021 had the Calorific Value shown. From July 2021 onwards, when the bill format changed, the CV hasn’t been given.


Just the point juliamc I have been making. Hold fire for now though as Ombudsman put me through to an OVO contact who actually did get back to me and is at the moment saying that because my bill jumped from quarterly to monthly, an actual bill was not produced, just an online summary. The are keeping an eye on the issue and are confident the CV will be on my quarterly bill. I will wait in hope;-))


For information on the calorific value discussion. I have approached my MP and this along with other anomalies have been provisionally agreed with. A letter has been sent to OVO by my MP recently, with response from OVO to my MP that they will be contacting me shortly. 

Will update when I can, may have to wait a while.

Sorry but I have just noticed this thread is marked as solved. From the posts no definitive answer has be given.

Does this mean the thread is closed as far as the forum is concerned or the questioners are satisfied, or it is solved as far as OVO are concerned?

 


This is a three year old thread and from memory, the answer originally posted was valid at the time. It has, however, been updated since then to reflect changes. Since this forum runs independently from most OVO stuff, the answers posted are never OVO’s official response unless it says otherwise. We try to get the OP to mark an answer but if seven days pass without that, we might mark an answer for them.

Both forum moderators and forum volunteers possess the power to mark any question as solved.

Ultimately, the National Grid Data Explorer can serve up the Calorific Value. You’ll just have to dig through https://mip-prd-web.azurewebsites.net/DataItemExplorer and find the right one.

Threads here don’t get closed for any reason except for moderation unless they get so badly outdated that it’s impossible to keep them.


Thankyou Blastoise186

You have answered who could “solve”  a discussion. If as you say  Both forum moderators and forum volunteers possess the power to mark any question as solved, would it be possible, obviously with just cause, for the same to unsolve a post?

Yes this a 3 year old thread but surely it is still live/valid as far as the CV data not being plainly available on bills over any period. A bill is a finite result of all criteria necessary to achieve a cost, as you know, so why are OVO avoiding this issue. For e.g. a monthly bill only one CV figure is needed, the average of CV’s given by National Grid over that period and if this is data used then why can it not be put on the bill? 

Yes, you are correct, I or any other OVO customer could dig through https://mip-prd-web.azurewebsites.net/DataItemExplorer, (dig being the operative word but surely that is the main point of the topic. Customers should not have to look/search for CV data used to calculate any bill. It should be in plain view, as it used to be. That also begs the question why, if OVO did once show the CV, why have they stopped?


This is a three year old thread, so there’s no value in unmarking the solution. If you have a better one to propose, feel free to post it and a moderator can consider it. Otherwise, the existing one will remain marked as a solution as-is.

Threads very rarely get unmarked as solved here. It’s only done if the mark was added by accident or the answer given is completely inappropriate. In both cases, it’s more likely the answer will get reassigned to something better or the original answer fixed up.

And besides that, the chances of unmarking a solution on a long standing thread with over 3000 views at this point is extremely unlikely.

It’s otherwise best to keep the existing one unless something better is more suitable. That way, others coming here can at least get something useful. The needs of the many outweigh the needs of the few here.

You have to bear in mind that EVERYONE involved in a thread gets notified if the best answer is assigned or reassigned. It’s not fair on those users to get spammed with such alerts without a really good reason.


I have not in anyway said this thread shouldn’t be closed. All I am pointing out is that the original questions have not been given a definitive answer.

What CV figure are OVO using to calculate a bill and why is it not available on any bill as it used be? That question has not been answered.  A possible answer could be:- Forum members do not know therefore cannot  answer, or OVO Forum administrators could respond with, we are not prepared to give an explanation. That way it leaves it to customers to resolve this issue in other ways.

I will add that as a forum member, the only thing I can say is, I am unable to say why OVO will not give this information.


Sigh… It’s not like I haven’t explained this a thousand times

It’s most likely because of two different billing systems. The old one is going away and has a different format for bills than the new one. If you’d like to see changes to the new one, feel free to suggest an idea via https://forum.ovoenergy.com/ideas . It’ll likely yield better results than simply shouting into a void and ranting about it not echoing back at you.


I know this is an old thread but still OVO have not explained why the CV is not on the bill or even give the CV over the phone when asked., why they stopped putting the CV on the bills? Surely these are simple questions that are easy for OVO to answer. It is no good forum managers saying it can be looked up on the National Grid, not everyone can do that. I have done that and recorded all National Grid CV data, plus calculated rolling daily averages then at the end of my billing period will calculate that average, which is the one OVO should be using for my bill. If OVO do not respond sensibly by the end of the month (I have tried all avenues) I will be presenting the figures I have to OVO CEO to ask him to confirm or reject my data. Also he may be able to answer why nobody from OVO has responded, excepting only the forum volunteers who to date have not given a definitive answer. Probably because they can’t.

Below is an example of how the National Grid display CV data on a daily basis. As this so plain to see, I do not understand why OVO withhold the CV figures? 

                           

  


@JGANLEY I have added an idea so you can expand on it with further posts with more details

Then you can see how many customers on the forum think it should be a priority and vote for it. 

If you focus on posting on the idea that may help you i suspect, rather than posting on a variety on threads on the forum where your posts may get little attention. 

Obviously up to you. I don't work for ovo.

Hope that helps

 

 


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