Has The Formula For Calculating Gas Units Used Suddenly Changed?

fallen121

On my British Gas bill for May the calorific value was stated to be 39.6. On my August bill it’s 39.7. Has the formula changed? I thought there were industry standards that governed how these things were calculated? If companies can amend these formulas at will, the amount of gas we use can be whatever they say it is. Is this another example of bill manipulation?

Mstty

No the formula is the same you just have to input the calorific value(which changes) from your bill. The gas provided is in a sense richer (let me Google the right term) so they supplied you superior gas which costs less to burn and you pay for that superior calorific rich gas.

"High-calorific natural gas or gas with a high calorific value . This gas contains relatively large proportions of higher hydrocarbons and consequently has more energy than low-calorific gas."

molerat

The calorific value, which is the quality of the gas in the pipes, is measured daily (actually multiple times daily within your local distribution zone) and the average is used for billing.  It is always changing and has always been the variable element of the bill.  If it was constant we would be charged by meter units rather than kWh. You can find the measured figures here https://mip-prd-web.azurewebsites.net/DataItemExplorer/Index

Robin9

No change - the CV varies almost by the hour depending on the mix of the sources of the gas

JGB1955

The CV can be anything between 38 and 41 - see Gas meter readings and bill calculation - GOV.UK (www.gov.uk)

wild666

fallen121 said:

On my British Gas bill for May the calorific value was stated to be 39.6. On my August bill it’s 39.7. Has the formula changed? I thought there were industry standards that governed how these things were calculated? If companies can amend these formulas at will, the amount of gas we use can be whatever they say it is. Is this another example of bill manipulation?

The CV (calorific value) changes almost daily and your monthly gas bill is worked out using an average for the month. 

[Deleted User]

The higher the calorific value of the gas supplied, the greater the heat output is from a given volume of gas. 

Gas comes from a variety of sources. Liquid Natural Gas from the Middle East, for example, can have a calorific value of up to 56. It will be added to the gas grid in small amounts to ensure that the calorific value of the gas supplied to your home is kept within prescribed limits.

As you are being billed for kWh, there is no supplier manipulation. It would be different if you were just paying for a cubic metre of gas which had changing calorific values. The policy on calorific values is as below:

https://www.ofgem.gov.uk/sites/default/files/docs/2014/08/supplier_guidance_on_cv_calculation.pdf

Note that the calorific value used is the AVERAGE of the gas supplied during the billing period TRUNCATED to one decimal place: that is, an average of 39.775 would be billed as 39.7.

You can view, and check,  the calorific value used on your bill by looking at this website:

https://www.nationalgrid.com/gas-transmission/data-and-operations/calorific-value-cv

I would interested to know what other examples you have of bill manipulation?