Swindon based npower has become the first supplier to raise prices on its standard energy tariffs. Prices will increase by 17.2 per cent for gas and 12.7 per cent for electricity. This will add around £159 to the average bill.

Because this move follows a steady rise in wholesale energy prices, the other major suppliers are expected to follow suit.

Karen Darby, founder of SimplySwitch, the price comparison and switching service, said: "Historically, when one of the big suppliers increases prices, the others are quick to follow. Analysts were predicting gas price rises of around 15 per cent.

"However, if the other suppliers follow npower's lead and raise prices by more than 17 per cent, householders will really feel the pinch.

"Fortunately, for those wishing to protect themselves from price rises, there are still some competitive capped deals available. Several providers have already stopped selling, or raised the price, of their capped tariffs.

Luckily however, there are still some available that offer good savings and charge no penalties if the customer wishes to leave.

"New Year's resolutions are often hard to keep as they require a great deal of effort and willpower. One that's quick and simple is reviewing your energy providers. By using a switching service, the whole process takes less than ten minutes and, with other price rises expected, it could save you a great deal of money."

To find and compare the cheapest deals, call 0800 781 1212 or visit simplyswitch.com.