Cheaper energy tariffs are not being promoted to customers, which is profiting the companies, an expert claims.
Paul Schofield of comparison website moneysupermarket.com said that the average household could save about £150 a year by switching to a cheaper energy plan.
He noted that six of the big energy companies had introduced cheaper tariffs in the last six months and called for an industry equivalent of the banking code to protect customers.
"The need for a banking-style code is obvious with our research finding over 60 per cent of Brits oblivious to whether or not they are on the cheapest deal," he added.
He went on to say that older tariffs were costing customers about £2.5 billion a year.
British Gas has announced an increase to gas and electricity prices of 13 per cent and 15 per cent respectively.
Tim Wolfenden on uSwitch.com suggested that this could be a "sign of things to come".
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