Changes to energy consumption figures used to calculate Ofgem's Supply Market Indicators

Press release

Publication date

Industry sector

Supply and Retail Market

Ofgem has today updated its estimates of how much gas and electricity consumers use on average per year. These figures are part of the data set used to produce Ofgem’s weekly Supply Market Indicators (SMI).

We keep all components of the SMI under review and update them as necessary. After consulting with stakeholders we have decided to lower our estimates of consumption. This is because data published by the Department for Energy and Climate Change this year shows a sustained fall in consumption in recent years, especially household gas use. The Office for National Statistics also recently highlighted this trend. Further information on their findings can be found on the Office for National Statistics website.

More information on these changes and the effect they will have is available on our Supply Market Indicators webpage.


1. The SMI shows an up-to-date estimate of the annual bill for an average dual fuel customer on a standard tariff, together with information about the costs a representative supplier faces for buying and delivering energy. The SMI also provides an indicative annual net margin for suppliers. This is the difference between consumers’ bills and the suppliers' costs. This information makes the market clearer by helping consumers understand trends in retail costs and bills. Using the new gas and electricity consumption figures, Ofgem estimates that the annual net margin of a representative supplier for a customer on this tariff is £65, compared with £90 using the previous consumption figures. 

2. Ofgem is the Office of Gas and Electricity Markets, which supports the Gas and Electricity Markets Authority, the regulator of the gas and electricity industries in Great Britain. The Authority's functions are set out mainly in the Gas Act 1986, the Electricity Act 1989, the Competition Act 1998 and the Utilities Act 2000. In this note, the functions of the Authority under all the relevant Acts are, for simplicity, described as the functions of Ofgem.

For further press information contact:
Chris Lock: 020 7901 7225
Out of hours: 07766 511470