By Roger Harrabin BBC Environment Analyst

Some doubt the ability of the UK to meet renewable energy targets

Britain's energy systems are no longer fit for purpose, according to leading members of the UK's best-known scientific academy, the Royal Society.

A meeting of experts at the society said the government must invest hugely to create a new low-carbon economy.

And it must take on the big generating companies who dominate energy policy, participants said.

The government says the key issues on energy will be addressed in its forthcoming energy White Paper.

Electricity 'supergrid'

The experts say ministers must make up lost time by investing massively in research and deployment of renewables; creating a more wide-ranging electricity 'supergrid'; and ensuring that coal-fired power stations capture 90% of their carbon emissions by 2020.

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One leading member of the society said privately that the government's performance on carbon capture so far had been pathetic - although would agree that criticism should not be confined to the UK.

The meeting agreed that failure to develop renewables in time meant that the UK must continue to rely on nuclear power - even though questions over waste and security were unresolved.

First priority on the society's action list is a big push on energy efficiency in existing homes, taking advantage of the latest technologies.

The call is echoed by the all-party parliamentary climate change group, which is set to insist that landlords should be prevented from letting homes which waste energy.

White Paper

The group's vice-chairman, Lord Redesdale, said the UK would never reach its climate change targets unless it radically improved policies on existing homes.

He said: "A billion tonnes will have failed to be saved from domestic carbon emissions and this is equivalent to the CO2 pollution from Britain's aviation sector over the next 25 years.

"We can either heat our homes and have hot baths, or fly but not both. There really does need to be much tougher policies on reducing carbon emissions from the homes."

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The government says many of the issues will be addressed in its energy White Paper - although to the frustration of ministers in the energy and environment departments, the Treasury has blocked whole scale investment in home refurbishment until after 2012.

Ministers argue that their policy on carbon capture and storage is ahead of any other major nation - calling for four demonstration projects and insisting that new coal-fired power stations should capture a percentage of their emissions until the technology is fully proven.

A Department of Energy and Climate Change spokesman said the UK had made major strides recently on energy and climate change.

He listed The Climate Change Act, carbon budgets, and leadership for the Copenhagen climate summit - including the Prime Minister's suggestion last week that rich nations should transfer $100bn-a-year to poor nations to help with climate change.