Great information I wish I had known this earlier; a year and a half ago my bill with EDF went from £50/month on a direct debit to £60 and then £80.
By March 2014 they wanted to change it to £164 a month despite my constant complaints that something must be wrong!!!
I asked for a second meter to be fitted and they told me my meter was fine and it would cost me £1000 for them to check my meter and fit a second one.
They told me that an average bungalow would use £1,500 electricity a year, despite the fact I have solid fuel heating.
The only way I got the meter changed was to refuse to pay and they fitted a key meter.
Surprise surprise every week since has been £14.50-£15.00 with no fluctuations and thats on a higher tariff than I was before.
Any ideas how i can now challenge them for a refund??
An electrician who used to fit meters told me that some of the digital ones are 10-20% out on accuracy - this is all wrong, yet I was made out to be the person at fault.