Recent price rises by gas and electricity firms are not justified and the Competition Commission should investigate, a watchdog has said. Three energy companies have raised their prices by an average of 15%, affecting 27 million consumers.
They blame soaring wholesale energy prices but Energywatch says the market is not competitive enough and consumers are paying over the odds.
Regulator Ofgem insists that the UK energy market is competitive.
Energywatch says it is impossible to calculate how much excess profit energy suppliers are making because they are not transparent about what they pay.
Allan Asher from Energywatch told BBC News 24 that the entire energy market should be reviewed by the Competition Commission.
He said: "The price rises we've seen are not justified.
"There'll be more, but sadly the market is not working well and that's leading to consumers paying much, much more than they need to."
The UK market is dominated by six providers - Npower, EDF and British Gas are the companies which have recently raised their prices and rivals are expected to follow suit in coming weeks.
British Gas, the UK's biggest power provider, announced that it would increase the amount it charges for gas and electricity by 15%.
The move followed increases by Npower, which raised its electricity prices by 12.7% and gas by 17.2%, and EDF Energy, which put up its electricity tariffs by 7.9% and gas bills by 12.9%.
The National Consumer Council warned last year that the government's target to end fuel poverty amongst vulnerable consumers by 2010 may be missed.
The NCC said unless energy suppliers were forced to reduce prices for low income consumers then fuel poverty numbers would not fall.
But Russell-Hamblin Boone from the Energy Retail Association insisted that the prices set by energy companies were fair.
"We have the most competitive market in the world, and it's important to recognise that there are lots of additional costs as well as just the wholesale price cost that are now being incorporated into our bills," he added.
BBC NEWS | Business | Energy price rises 'unjustified'
Note: I remember as a kid hearing on the news every winter, about old people dieing because of the cold and that they couldn't afford to put the heating on. If the prices keep rising the way we are, even with the old peoples heating allowance, the prices will mean that once again we are hearing about such things on the news. The difference this time though is that it's not just old people not being able to comfortably afford to heat their homes, it's anyone on a lower than "average" family income. I mean, they are moaning about global warming and expect people to pay out extra green taxes to help slow it down, yet they are constantly putting up prices on heating bills.... It don't figure to me, they aint getting it both ways, either they keep the utility bill levels down, or people will be saying "bring on the permenant globally enhanced summer".