Three million British customers of French-owned EDF Energy will soon pay almost 11 per cent more for their gas and electricity.
The energy giant announced today it will hike average bills by 10.8 per cent from 7 December, prompting fresh accusations of profiteering from critics.
The firm is the fifth of the Big Six energy firms to announce massive price increases in recent weeks, all timed to have the maximum impact right at the start of winter.
The news prompted Labour's shadow energy secretary Caroline Flint to point out that millions faced "a winter of misery as EDF clobber households with above-inflation price rises at the very time they can least afford it."
EDF's increase is the largest of the recent increases, forcing customers of the firm to pay an extra £130 a year to heat and light their homes.
With a fair degree of understatement, EDF director Martin Lawrence, said: "We know that customers will not welcome this news."
But he did proudly point out that the new prices will be cheaper on average than those of all the other major suppliers which have announced standard price rises so far this autumn.
In fact that simply fuels claims that the Big Six energy firms are working in collusion, with only £36 separating the average tariff prices of the companies that have announced hikes so far.
"People will not understand why EDF are hiking up their bills by so much when they made nearly £1.6 billion in profits last year," said Caroline Flint.
The recent wave of energy price hikes has piled an extra £753m onto household energy bills and tipped a further 314,000 households into fuel poverty, according to uSwitch.
"The impact of higher energy prices on households is immense," said Ann Robinson, director of consumer policy at the comparison site.
"Because energy is such a basic need, you cannot have a winter price hike without casualties. The most visible are the seven million households who will now be living in fuel poverty, but there will be hidden victims too, many of whom will be gambling with their health or well-being as they turn their heating down or off in response to higher prices."
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