Profits for the Big Six energy companies have leapt to more than one billion pounds since 2009, according to regulator Ofgem
The figures show that together British Gas, E.ON, EDF, npower, ScottishPower and SSE recorded underlying earnings - before interest payments and tax - of £1.19 billion in 2012, up from £221 million in 2009.
But TUC General Secretary Frances O'Grady said: "Ofgem show excess profits are the real source of soaring energy bills.