IMPROVEMENTS in energy efficiency will lead to greater use of fossil fuels, according to research published this week.

Terry Barker, director of the Cambridge Centre for Climate Change Mitigation Research, predicts that by 2030, half the carbon emission savings gained from more fuel-effi-cient transport, buildings and industry will be cancelled out by a corresponding rise in consumption of fossil fuels.

He argues that what he calls a “rebound effect” has been seriously underestimated by policymakers, who will have to impose drastic measures such as high petrol taxes to tackle the problem.

“The rebound effect is not very welcome to politicians because they have been thinking that energy-efficiency programmes are the answer to climate change,” said Barker, a co-author of reports by the International Panel on Climate Change. “It’s not nearly as good an answer as they thought. Efficiency programmes will have to be ramped up to achieve the same targets.”

Steven Chu, America’s energy secretary, told the BBC this month of plans to make commercial buildings in America 80% more efficient and the European Union has set a target of a 20% reduction in overall consumption of fossil fuels by 2020.

The rebound effect works in several ways. Industry, for example, will save on fuel costs by taking measures such as insulating buildings or switching to hybrid cars. It can then pass the savings to customers through lower prices, leaving them with more cash to spend. Production will rise to meet the demand created by the extra spending.

Barker said the effect will be much stronger in the developing world, where large populations are about to join the fossil-fuel economy and small improvements in disposable income can lead to big changes in consumption.

He believes that energy-effi-ciency policies must be accompanied by measures to keep the price of fossil fuels high, limiting the rebound effect and encouraging a move to clean fuels that do not produce carbon, such as solar and wind power.

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