A new report has suggested up to four million households in the UK may have overpaid on their energy bills due to faulty meters.
Consumer watchdog Which? has claimed up to 3.9 million households on tariffs that charge different rates depending on the time energy is used could be out-of-pocket if their meter clock is inaccurate.
A retired engineer from South Wales, Gary Day, actually informed Which? of the issues surrounding certain meter clocks after he found the meter in his house, as well as at three of his neighbours were all inaccurate.
As a result of finding the error, Mr Day was then refunded £2,300 by his energy supplier Swalec, part of 'Big Six' energy supplier SSE.
Speaking to Which?, Mr Day said: "I have only checked four meters and every single one of them was wrong. "The problem is most consumers don't go around checking, and we are at a disadvantage because of that."
A Which? spokesperson added: "Having a faulty clock on your energy meter could leave you hundreds of pounds out-of-pocket.
"It's the supplier's responsibility to ensure they are correct so if you suspect there might be a fault then contact your energy company."
Tariffs such as Economy 7 or Economy 10 typically charge consumers less for using the power at night when energy demand is usually lower.
Unfortunately for energy consumers, energy suppliers do not have to check the accuracy of meter clocks when taking readings. The onus instead falls on the consumer to notice faults as Mr Day did.
An Ofgem spokesman said: "If consumers suspect that their electricity meter is faulty their supplier is required to investigate and make best efforts to resolve the problem.
"If necessary, as a final option the supplier will make arrangements for the meter to be verified by a meter examiner appointed by National Measurement Office."
If you think you may be paying too much for your energy bills, there are many other reasons that could cause this. Take a look at our page - why are my energy bills so high - for more info.
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