Npower has become the fourth of the Big Six energy firms to announce a winter energy price rise in a further blow to households already suffering during the Big Freeze.
Millions of households faced with winter energy price hikes can use a little-known loophole to maintain existing costs, as long as they then switch supplier.
British Gas owner Centrica today revealed profits are set to be higher than expected, just days after the firm announced an energy price hike for eight million households.