Smart meters could leave millions of Brits facing higher energy bills, it has been claimed.
The cost of electricity may have to go up as a result of the government's failure to accurately predict the cost of putting a smart meter in every home in Britain.
According to Ernst & Young, the government has estimated the cost of the national installation scheme would be £9 billion, however, the firm believes the real cost could be as high as £13.4 billion.
Ernst & Young utilities expert, Tony Ward, said: "Very big and complex projects of this sort always cost more than anticipated."
He claimed that energy firms should put up their fair share to ensure the scheme is successful and not just pocket the benefits.
Every UK household is expected to be fitted with a smart meter by 2020, paving the way for a low-carbon smart energy grid.
The new meters will send and receive information on energy consumption, making estimated bills a thing of the past.
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