energy a step closer. a uk laboratory has smashed the record for generating energy from a nuclearfusion reaction. here's justin rowlatt. two, one, zero. this is the record—breaking reaction. it is more than 150 million degrees celsius. ten times hotter than the heart of the sun. and it happened here, the world's most powerful fusion plant, jet fusion, in culham in oxfordshire. it is, says the team here, a landmark for this technology. these results are really significant because what we have managed to demonstrate insidejet is we can create a mini sun, the right kind of mini sun, hold it there for a sustained period and get really good performance levels, which is a major step forward in terms of our quest to get to fusion power plants. most nuclear reactors use fission. that's when big, unstable atoms like uranium are split in two, releasing lots of energy and radiation. fusion is different.