When pressed, Stephen Tetlow, chief executive of IMechE, offered the example of coal-fired power stations.

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Cuadrilla, the firm licensed to drill fracking in the UK, said its figures tallied with the IMechE.

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The marketing of the IMechE document will be seen by some as inflammatory.

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Highview believes that, produced at scale, their kits could be up to 70% efficient, and IMechE agrees this figure is realistic.

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The IMechE says this is the opening salvo in the debate about re-defining the UN's Millennium Development goals, which are up for review in 2015.

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The Institution of Mechanical Engineers (IMechE) said jobs created by fracking, a form of gas extraction, included chemical, mechanical, civil and structural engineers, operations staff and geologists.

BBC: Fracking could create 'thousands' of engineering jobs

IMechE says the simplicity and elegance of the Highview process is appealing, especially as it addresses not just the problem of storage but also the separate problem of waste industrial heat.

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IMechE says this process is only 25% efficient but it is massively improved by co-siting the cryo-generator next to an industrial plant or power station producing low-grade heat that is currently vented and being released into the atmosphere.

BBC: Liquid air 'offers energy storage hope'