AN independent Scotland would have to rely on power from England to keep its lights on under Alex Salmond's renewables plan, Ed Davey, the UK Energy and Climate Change Secretary, warns today.

Mr Davey raised fears over the First Minister's renewable energy vision. He suggested it would be a false hope under independence and would lead to higher bills.

"I'm always a bit mystified by some of the things I hear from the SNP," said the Liberal Democrat Secretary of State. "They talk of a 100% renewable energy sector in Scotland. I'm someone who is very ambitious on renewables and keen to see Scotland meet its ambitions. But we all know renewables have different characteristics to other types of energy. One of them is that they are intermittent.

"That means you need a mix, a diversity. So Scotland, if it was 100% renewable, might be less energy secure if it did not have the links with the rest of the UK and might have to buy baseload and more flexible load from the UK, if it really went for 100% renewables. For an independent country to have to rely on another country for baseload and flexible generation looks highly risky."

Mr Davey said energy bills and the danger to energy security would be much higher.

"Imagine Scotland has 100% renewables and the wind doesn't blow and it needs to import electricity from the rest of the UK and the rest of the UK has quite tight margins itself; there's a cold snap, the wind's not blowing and we are using all our power stations to meet our demands. Could a Scottish Government be sure that energy would flow north?

"It would only flow north if it paid a very high price for it. There's a danger of insecurity and high bills that's baked into this model."

So asked if Scotland would have to rely on English power to keep its lights on, the Energy Secretary replied: "I fear so. The ambition of 100% renewables is easier to achieve within the UK."

Mr Davey made clear the shared single energy market across the Union would end with independence. "Scotland as an independent country would not expect the English, Welsh and Northern Irish energy consumers to pay the bill for subsidising another country. We don't subsidise remote, rural communities in Norway. We wouldn't do that in Scotland. We're very happy to do that in the UK.

A Scottish Government spokesman said: "The basis of the claim is not an accurate reflection of Scottish Government policy. The 100% target is for the equivalent of 100% of energy demand in Scotland supported by a mix of generation and technologies. To say Scotland will be relying solely on intermittent renewables for all of its own-source electricity is incorrect."