British Gas owner Centrica hopes a scheme to offer free electricity on Saturdays will encourage households to use electrical appliances at the weekend, when industrial demand is lower.
The development came as Centrica hinted at further price rises as British Gas announced profits from its residential arm rose by 3.2 percent, thanks to the freezing spring weather.
Earnings increased to £356 million during the first half of 2013, as the company cashed in on the bitterly cold temperatures after raising tariffs six percent at the end of last year
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Five people have died on the M6 in Staffordshire after a crash involving a lorry and a car.
The company posted a 63.5% plunge in bottom line pre-tax profits to £176.4 million on a comparable 52-week basis.
Through the day, most of the cloud should break up to leave fine conditions for many with spells of sunshine.