Npower has announced that it will be raising the price of gas by 15.7 per cent and electricity prices by 7.2 per cent from 1 October.
The company has blamed the instability of the energy market for its price rises and blamed the 'volatile global wholesale market' for the announcement.

Customers with a dual fuel tariff should expect to see prices rise by 12.2 per cent from October, with the average standard monthly direct debit dual fuel customer seeing an increase of 37p per day.

The company have also said that the new rates are on average £30 per year cheaper than British Gas, and cheaper than any other supplier who has increased prices on the same basis, based on average annual consumption*.

E.On most recently announced prices rises from 13 September by 18 per cent for gas, and 11 per cent for electricity. British Gas has said it will increase prices by 18 per cent for gas and 16 per cent for electricity, and Scottish & Southern Energy (SSE) and Swalec will also increase gas by 18 per cent and 11 per cent for electricity.

Kevin Miles, of Npower said: 'I know it hurts everyone when we put up prices and I wish we did not have to. Although our half year profits were better than last year they do not begin to match the billions of pounds we are investing in energy for the future.

'With reduced quantities of North Sea gas, we are now forced to buy energy on the volatile global wholesale market. World events have pushed up prices and we believe this trend will continue. In the UK we have also seen rising distribution and network charges, and further environmental costs but we have still managed to keep our increases lower than those announced by any other major supplier.'

EDF alone remains among the major suppliers to have not announced price rises recently.

*Assumptions are based on the following calculations:

• Average increase per day - Prices based on average annual consumption of 16,500 kWh gas and 3,300 kWh electricity payment via monthly direct debit. Previous national average price £1,054, NEW national average price £1188. £134/366 = 37p inclusive of VAT
• npower standard MDD DF v British Gas standard MDD DF - Average national price based on Ofgem average consumption 16,500kWh gas and 3,300kWh electricity – npower £1,188 / British Gas £1,219
• Cheaper on average than any other major supplier which has increased prices this summer - based on standard monthly direct debit dual fuel at Ofgem standard average consumption of 16,500 kWh gas and 3,300 kWh electricity. Prices averaged across Britain.