A milder winter and energy efficiencies helped British Gas profits tumble by 26% in the first half of 2014.
Parent company Centrica predicts average bills will fall by around £90 this year because consumers are not using as much power.
However, industry regulator Ofgem has suggested that it sees power companies doubling their profit margins in the second half of the year.
They have already referred the Big Six energy companies to the competition authorities.
ITV News Correspondent Nina Nannar reports:
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