SCOTTISH Power will no longer burn fossil fuels to generate electricity.

The Spanish-owned giant has become the first major UK energy supplier to refocus entirely on renewable sources such as wind and solar.

Its move comes a week after the International Panel on Climate Change (IPCC) warned the world was "off track" in efforts to limit environmentally catastrophic global warming.

IPCC scientists warned "rapid, far-reaching and unprecedented changes in all aspects of society" were required.

Scottish Power on Tuesday said it had sold its remaining conventional electricity generation business to a subsidiary of Drax Group for £702m.

And it said it would invest £5.2bn in UK to more than double existing 2 gigawatt capacity for renewable energy over the next four years.

Ignacio Galán, Chairman and Chief Executive of Iberdrola, Scottish Power's parent, said: "Energy companies must be part of the solution to climate change.

"Iberdrola is acting now to cut carbon emissions 30 per cent by 2020 and be carbon neutral by 2050. The sale of these generation assets is consistent with our strategy."

Keith Anderson, chief Executive of Scottish Power, said: "This is a pivotal shift for Scottish Power as we realise a long-term ambition. We are leaving carbon generation behind for a renewable future powered by cheaper green energy. We have closed coal, sold gas and built enough wind to power 1.2 million homes.

"Every working day we are investing over £4m to deliver cleaner, smarter power for customers. From today we can focus solely on making energy generation cheaper, cutting carbon quicker, building smart grids and connecting customers to renewable electric future for transportation and heating.”

Over the last decade Scottish Power has closed all of its coal plants.

The sale to Drax is of its remaining gas and hydro stations.

Scottish Power has 2,700 megawatts (MW) of wind power capacity operating or under construction in the UK, and a pipeline of future projects capable of generating more than 3,000 MW.

Drax has Britain's biggest power plant in North Yorkshire, which burns coal. It has converted some of this capacity to wood chips. It has until 2025 to limit emissions.

Its chief executive Will Gardiner said: "We believe there is a compelling logic in our move to add further flexible sources of power to our offering."

The deal must be approved by Drax shareholders.