The 'Big Six' energy suppliers have been criticised by a campaign group following the release of new figures suggesting the firms have doubled their retail profit margins.
Figures from Ofgem suggest in the last 18 months the main energy firms have more than doubled their retail profit margins, raking in an average of Â£95 on household dual fill bills - much to the disdain of Fuel Poverty Action.
Sam Robertson, a campaigner with Fuel Poverty Action, said: "This cold-blooded profiteering has to stop, but piecemeal market reforms will not go far enough, especially given the threat of a dash for gas that will send bills through the roof."
Shadow energy and climate change secretary, Caroline Flint, also criticised the energy firms.
She said: "Energy companies always claim that when they put up people's bills they're only passing on increased costs. What these figures show once and for all is that energy companies have increased their profits on the back of spiralling bills for hard-pressed consumers.
"These companies like to pretend they are the victims of wholesale prices, but they have been allowed to arrange their businesses in a way that enables them to make huge profits whatever the cost of wholesale energy."
Between October 2012 and January 2013, all of the 'Big Six' increased their energy bills, citing a number of reasons including the cost of wholesale power and other rising costs.
However, a spokesman from Centrica, the parent company of British Gas, said the firm had averaged a five per cent return on profit margins on its retail market for the past five years, adding it averaged out to Â£50 per customer.
Similarly, SSE in its corporate profile suggested: "We expect to make a profit margin of around five per cent in energy supply over the medium term, which we believe to be fair and sustainable."
To help customers find ways in which to make their homes more energy-efficient and reduce their energy bills, the Government and energy suppliers are also working together as part of the Green Deal scheme. Customers can receive subsidies on things such as boiler replacements and wall insulation, paying off the loan as part of their energy bill.
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