Tax-dodging utility giant nPower will rake in nearly £4,000 profits in the time it takes you to read this page, but that won't stop it raising dual-fuel bills by more than 10 per cent.

The reviled energy retailer brushed off public outrage yesterday as it announced plans to squeeze freezing households even harder from December, with the average fuel bill rising £137 to an eye-watering £1,459 a year.

Electricity tariffs will rise 9.3 per cent and gas 11.1 per cent as winter sets in - a 10.4 per cent rise for dual-fuel customers.

Chief executive Paul Massara conceded that higher prices were "always unwelcome," adding that the decision wasn't "taken lightly."

He said: "We only aim to make around five pence in every pound in our retail business which we feel is a fair return for delivering reliable energy to consumers and for the risks that we bear."

But Fuel Poverty Action's Clare Welton said the "big six" energy suppliers "conveniently" overlooked fat profit margins by their parent companies' power generation projects.

The firms' power generation profits average more than 24 per cent in 2011, with much of that cash coming from the high transfer prices charged to each group's own retail subsidiary.

"As yet more households are pushed into fuel poverty we need to acknowledge that the problem is the big six themselves - they will never prioritise people's lives over their profits," said Ms Welton.

She called for a "total overhaul of the system" - putting it under democratic control, and introducing publicly and community-owned renewable energy production and distribution.

"This is the only way we will see sustainable, affordable energy into the future," she said.

NPower's tariff rise follows operating profits last year of £390 million - a rate of roughly £742 per minute.

The brand also took a bruising in April when activists revealed the company had dodged an estimated £100m in corporation tax through a complex web of inter-company loans and a postbox in Malta.

MPs grilling Mr Massara learned that nPower had paid no corporation tax between 2008 and 2011, with the CEO insisting that capital investments had simply wiped out its profits.

But the company's records showed that nearly all of its £2.7 billion in loans from its own parent company RWE arrived via Maltese subsidiary Scaris Ltd.

NPower's profits were then forwarded as interest on Scaris loans, allowing Scaris to pay back RWE - incurring as little as 5 per cent in dividends tax under Maltese law, compared to Britain's then corporation tax rate of 26 per cent.

The £100m tax gap equates to around 71 per cent of nPower's total contribution to the government's underfunded Warm Homes Discount scheme, which provides a £135 discount on winter fuel bills for poor households.