Cooling towersThe Treasury should drop its free market "dogma" and invest billions in nuclear power stations and renewables, a former government chief scientist has said.

Professor Sir David King warned that without Government intervention, the private sector would not deliver the huge sums needed to keep the lights on and end the UK's dependence on imported fossil fuels.

He said Government-led investment in major low-carbon energy infrastructure would reboot the economy following the financial crisis and de-couple it from fossil fuels. For example, there is a need to move road transport from petrol to electricity, which would require a new generation of nuclear reactors to cope with increased demand, he said.

But passively letting the situation unfold would see major energy companies building new gas-fired power stations, which would leave the UK dependent on imported gas, at the whim of exporting countries and facing rising costs as global demand for gas pushes up prices.

"I think the Treasury feels this is up to the market to deliver, but actually this isn't going to happen. Infrastructure on this scale is going to need public-private partnership with strong Treasury intervention to signal where the investment should take place," he said.

He said the Treasury and No 10 needed to grasp the problem, as it was not enough to leave decarbonising the economy up to the Department of Energy and Climate Change. He called for the Government to "pump prime" the process of investing in low-carbon infrastructure in the country's long-term interest.

Big infrastructure projects such as nuclear reactors or the Severn Barrage tidal energy scheme, which was ruled out by ministers as too expensive but could be back on the cards with private sector interest, would stimulate the economy and provide jobs, Sir David added.

The UK Government has legally binding commitments to cut greenhouse gas emissions and sees new nuclear build, along with renewables and technology that captures and stores carbon from fossil fuel power stations, as key to tackling climate change.

But a nuclear renaissance has faltered, with two of the "Big Six" energy companies pulling out of schemes to build reactors and French energy giant EDF warning it needs the electricity market reforms planned by the Government to boost investment in the sector to be robust to go ahead with its plans.

Sir David suggested "directed quantitative easing" could help stimulate investment in low carbon technology.