When Caroline Strover received a quarterly electricity bill for £6,000, it was initially blamed on a misplaced decimal point.

But energy company EDF Energy now says the bill is for the correct amount, as it had only recorded an estimated reading for the past four and a half years.

The meter had been read five times during that period but each time the meter reader rejected the reading as the figure seemed too high.

It now appears the energy consumption was correct and the four-bedroom house, which does not have a gas supply, was consuming an abnormally high amount of electricity.

The isolated house in Naccolt, near Wye, is being renovated and was heated with electric heaters during the winter.

Mrs Strover pays £65 per month by direct debit for the electricity, but her correct monthly usage requires a payment of about £175 a month which, with the underpayment over the last four and a half years, has left her in arrears of £6,663.44.

The energy company has offered to reduce this figure but Mrs Strover has now taken the case to the watchdog Energy Watch to see if she is liable to pay for the energy company’s mistake.

Mrs Strover said: “When the bill came it was a worry and then it was a laugh as it seemed the bill was a joke.

“It has now turned serious again and is becoming worse and worse.”

Richard Robinson, spokesman for EDF Energy said: “We have explained fully to the customer why the reading is so high and apologised for what has occurred.

“EDF Energy has also offered a gesture of goodwill to the customer for the inconvenience caused.”