Many energy suppliers are signing consumers up to fixed-rate tariffs that do not honestly reflect current prices, an expert has said.
Mark Todd, co-founder of energyhelpline.com, which helps consumers compare energy prices and switch energy providers, said scores of people are in lock-in tariffs, paying more than they really should.
Speaking to the BBC, he said consumers on certain gas and electricity deals could be losing out on more than £500 a year as energy prices fall.
"It can be really unfair because many of them don't reflect the market rate and some are up to £532 a year more expensive than the current market conditions," Mr Todd said.
"It can also be very confusing to get out of them and they can include big cancellation penalties, up to £100."
Audrey Gallacher, of Consumer Focus, urged consumers who are worried about being on fixed-price deals to switch energy providers in order to save money.
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