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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Cloudy and damp across much of England and Wales, although the rain should turn lighter and more patchy by the afternoon.
A British journalist based in Egypt has been expelled from the country as authorities tighten control over the media ahead.