Science News

Implosion Fusion - A New Approach to Nuclear Power

A New approach to fusion has been given the go-ahead near Oxford in the UK.

Nuclear fusion is the power source for the Sun and involves smashing nuclei of light elements, like hydrogen, together so they fuse, releasing lots of energy.  This is different from conventional nuclear power which involves splitting large atoms to release energy.

The problem with fusion is that keeping the nuclei close together when you give them the energy needed to react.  One way is to confine them using magnetic fields, this has been given funding recently in a project called ITER, but it's extremely difficult and expensive.

Professor Mike Dunne, of the Rutherford Appleton Laboratory, has a slightly different plan.  He has just been given the go-ahead to build a machine to compress and heat pellets of hydrogen with large lasers until they are hot enough to fuse.  When you hit a pellet of hydrogen with a laser, the outermost layer of the pellet heats up quickly and explodes, and this explosion forces the remains of the pellet together, compressing it down.  The technique of blasting hydrogen with lasers to cause fusion has been tried before but Professor Dunne's plan is to use one large laser to partially compress the pellet with a pulse of a few billionths of a second long, and then blast the pellet with a a very short laser pulse only a few trillionths of a second long.  This second pulse will trigger fusion.

If it works, this would be a non-polluting source of energy which could be virtually unlimited.

9th Sep 2007