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Inventor's creation not just hot air

2 October 2012 Last updated at 15:44 BST

An inventor has developed a system that uses liquid air to power engines.

Peter Dearman may have found an answer to one of the planet's biggest problems - its future energy supply - and now some of the UK's top engineers are trying to see if the system could be used to store energy from wind farms on a large scale.

Roger Harrabin reports.