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The Future of Renewable Energy is a Miniature Sun, and It’s Hidden in Southern England

posted 19 Oct 2011, 15:58 by Jamie Condliffe

Oil and gas might be running out, but renewable power sucks so much it counts for less than 10 per cent of all the energy we use. The answer? Recreate the sun using nuclear fusion, in a sleepy corner of the UK.

No, really. Over the past few decades scientists and engineers have been scratching their heads over how to solve our energy problems using the process that powers stars. In fact, Europe’s biggest nuclear fusion device, the Joint European Torus (JET), is leading the way, and it’s hidden away in the tranquil Oxfordshire countryside. “In effect we’re making a miniature version of the sun in the laboratory,” explains Nick Holloway from JET. But how the hell do they do it, and when will it be powering our laptops?
Alleviating Any Con-Fusion

To answer that, first a crash-course in nuclear physics using my love life as a metaphor. Much like many of my romantic encounters, fusion requires bringing together two objects that tend to repel each other. By joining two hydrogen nuclei, it’s possible to create a new helium nucleus, and simultaneously release serious amounts of energy. For some perspective, just 25g of hydrogen isotopes — the same weight as two iPod Shuffles — could produce enough electricity to last an average European a lifetime. Hear that, solar power?

The tricky bit, though, is getting those damned nuclei close enough to fuse, because they both have a positive charge which means they repel each other. The solution isn’t elegant, but it does work: throw enough heat at the hydrogen, and it becomes plasma — a hot soup of nuclei and electrons, with enough energy to overcome the repulsion. A bit like the lubricating role alcohol used to play in my romantic encounters. But, unlike my love life, the reaction needs to reach a scorching 100 million C to get going — which, if you’re wondering, is ten times hotter than the sun. So how on earth do they do that in a country where 20 degrees celsius is considered tropical?