Trade association Energy UK said in a statement that a fault in the pre-payment meters’ calculation affected all meters installed since 2007, adding 2 per cent to the cost of gas or around 25 pence extra per top up.
In a statement made late on Wednesday Ofgem called on suppliers to submit a timetable by the end of the week detailing how they will repay consumers, reconfigure the faulty meters and protect their customers from overpayment in the meantime.
“Suppliers must act quickly to resolve the problem in a way that treats customers fairly. We have not ruled out enforcement action,” said Ofgem’s senior partner for markets, Rachel Fletcher.
Utility Week understands that the faulty meters were manufactured by Landis+Gyr, with an incorrect calorific value code used to calculate the amount of gas used set on installation. Meters installed after 30 October this year are not believed to be affected.
A spokesperson for Energy UK said that the fault only came to light “a couple of weeks ago” when the problem was spotted by an “eagle-eyed” customer. The trade body then referred the industry to Ofgem when the extent of the problem was realised, the spokesperson said.
Energy UK chief executive, Angela Knight, said in a statement: “Suppliers are working hard to roll out a solution for an issue which has affected some pre-payment gas meters. The companies know who is affected and will be getting in touch directly to put the meters right and refund any money owed.
“The suppliers and the wider industry are all very sorry this problem has occurred but are already getting in contact with customers. Customers do not need to do anything, but, if they are concerned, just need to contact their energy company who will be able to help.”