Robert Hammond, energy expert for Consumer Focus, said: "There needs to be greater transparency of energy company accounts if consumers are to have confidence that their bills are justified, and are not just lining the pockets of shareholders."
He added: "We also believe there is generally room for further price cuts, which should be made now before winter bills hit consumers' doormats."
Yesterday Scottish and Southern Energy announced a 36 per cent increase in profits in the past six months. British Gas has also announced that it expects profits to increase this year by 43 per cent.
Last month another consumer group, Which?, called for greater clarity and transparency over energy prices.
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