The average monthly gas and electricity bill for large households is expected to jump to £742 from January, up from £246 in the same month this year. Someone on an average monthly income after tax of £2,615 will use around 28 per cent of their pay on energy. Those with medium-sized homes can use almost 20 percent of their income. Bills will soar when the government lifts the bill cap in October and again in January. The rising costs come on top of higher mortgage, gas, cell phone and shopping costs. The upper limit of the price of energy