Fusion Dawn - EarthRise

The dream of cheap,safe fusion power takes a step closer to become reality Broadcast 13/04/2012

Physicists have long joked that nuclear fusion is the power of the future - and always will be! But a new international collaboration is under way to make nuclear fusion a reality. Reporter Gelareh Darabi visits the site of ITER, a fusion reactor currently being constructed in France, and the JET reactor in the UK - both attempting to bring the power of the sun to earth.
A fusion reaction happens when two variants, or isotopes, of hydrogen - deuterium and tritium - fuse to form a helium atom and a high-speed neutron. This is the same reaction that powers the sun. In a commercial fusion power station the high-speed neutrons would be slowed down by a denser material surrounding the reaction. This slowly releases heat which can be used to produce steam and drive electric turbines.
However, sadly in reality it is not as easy as this. The challenge is to create a self-sustaining fusion reaction - one that gives out more energy than is required to start it. Just one of the problems is that the two types of hydrogen must be combined at a temperature of 100 million degrees Celsius inside a powerful magnetic field. Both require huge amounts of energy. The ITER reactor will not be turned on for at least another 10 years, and further research is needed to ensure that it is viable. Perry Beaumont
But the dream of free, safe and virtually limitless energy is worth pursuing.