Adam Scorer, the organisation's campaigns director, said as the best deals are available online, millions of low-income consumers without internet access and bank accounts cannot take advantage of them.
"It becomes little more than an academic exercise to point to the best deals in the market and to use these as the basis on which to calculate the savings that are available to low-income consumers," he explained.
"Exhorting consumers to switch to tariffs that are unavailable to them is not a plan of action."
Yesterday, figures released by Ofgem found that 5.1 million people changed their deals in 2007, the highest level of switching in the UK for five years.
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