The Labour party has slammed the UK's 'Big Six' energy suppliers, accusing them of overcharging customers a staggering £4bn.
In research analysing comparative energy market data, it claims the six major energy firms overcharged the average household more than £48 a year over the last few years.
Shadow energy secretary, Caroline Flint, said: "These figures reveal the full extent of the way consumers have been overcharged for their electricity.
"Energy companies always blame wholesale costs when they put up bills, but it now looks like they've deliberately inflated prices to boost profits from their power stations."
Disgruntled energy consumers have long voiced their objections to increases in their energy bills, but were unable to stop SSE and British Gas starting the ball rolling with the latest wave of price rises of 8.2% and 9.2% in November respectively. E.On was the last of the firms to confirm a price hike, with the firm set to increase bills 3.7% from January 18, 2014.
In order to conduct its research Labour was provided information on the average market price of energy for this year by independent supplier, First Utility. It was then able to compare this with the price the energy suppliers paid for their supply from power stations.
The research concluded this resulted in energy consumers being overcharged £3.8bn in the last three years, with suppliers overstating the actual cost they paid for wholesale power from power stations.
Energy UK, the representative of the UK's energy suppliers, denied Labours claims however, arguing the figures were not directly comparable and wholesale energy prices covered a lot more than simply the cost of energy itself.
An Energy UK spokesperson said: "Energy suppliers pay the most competitive price they can for the gas and electricity they purchase.
"The overall costs of wholesale energy ... include a number of costs so are not purely market prices. Also, as suppliers buy their energy ahead so its there when customers want and need it, averages in this area don't give the true picture."
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