In the early 70s, Rob Goldston was a graduate student in plasma physics, and experiments to produce fusion energy were just starting to bear fruit.
“We had a huge party because we had made 1/1000th of a joule of fusion energy,” he told me. “It was ridiculous, it was a tiny amount of energy.” A 35-watt light bulb, for instance, uses 35 joules every second. Now, 40 years later, the game has changed. A recent experiment at the Joint European Torus fusion reactor in the United Kingdom produced 20 million joules. And the National Ignition Facility in California just reached a milestone by producing more energy in a fusion reaction than was needed to start that reaction.
In other words, scientists today are much closer to creating fusion energy than they were 40 years ago. And while most large public research projects are still decades from producing a reactor that can compete in the marketplace, a number of private companies have jumped headlong into the fusion race. Propelled by advances in engineering and science, changes in public funding, and tens of millions in high-risk high-tech investment dollars, they’re betting they can create a scalable, sellable reactor in less than a decade.
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http://motherboard.vice.com/blog/the-nuclear-fusion-arms-race-is-underway