Major Nuclear Fusion Breakthrough Achieved by European Scientists

The experiments produced 59 megajoules of energy over five seconds (11 megawatts of power).
The significance is that it validates design choices that have been made for an even bigger fusion reactor now being constructed in France.

“The JET experiments put us a step closer to fusion power,” said Dr Joe Milnes, the head of operations at the reactor lab. “We’ve demonstrated that we can create a mini star inside of our machine and hold it there for five seconds and get high performance, which really takes us into a new realm.”