A little tale.... In 1982 I attended a long job interview at the JET (Joint European Torus) nuclear fusion project at Culham in Oxfordshire (UK).
As part of the interview, I was given a tour around the facility, acompanied by one of the engineers who could explain the equipment and (hopefully) answer my queries. It was interesting stuff – and the massive machine itself was very impressive. At the time, they were part way through building the vacuum chamber and were installing some of the huge magnet clusters. Everything smelled of Big Money – the whole project looked like some Hollywood SciFi movie view of “the future”. I was told about the difficulty in pulling a hard enough vacuum for the proposed experiments – about the levels of purity, and freedom from contamination, needed in the plasma – about the possible instability of the plasma ring, and the physical “limiters” that were meant to hold its writhing in check – about how the slightest touch of the snaking plasma against the walls of the chamber would vaporise metal and poison the mix (requiring even higher temperatures to achieve fusion) . Then I asked why, if contact was forbidden between wall and plasma, the limiters were designed to touch? And surely that would mean that the plasma could never achieve the desired purity. He thought for a while, and couldn't really answer – but agreed that it seemed illogical. I was also told about the enormous neutron flux expected as the plasma apprroached (and hopefully achieved) fusion. And how this flux was so large that it would seriously degrade all the wiring insulation – including the insulation in the electromagnets – resulting in a finite number of pulses before the magnets would be totally trashed. I asked whether this was a rather fundamental flaw in the design, since a device that ruined its own magnets could never be used to generate power – even if it was able to achieve a positive energy balance. His only answer was that they would just have to cross that bridge once they had reached it (maybe by somehow sheilding the magnets!) I came away with the unseasy feeling that the whole JET project was some sort of elaborate fraud – a way for governments to delay decisions on energy policy by allowing them to point at the huge budget and say “look – the future is sorted!”, whilst continuing to allow themselves to be schmoozed by the vast fossil fuel lobby. One very real effect was to starve fission reactor research of development funding. After all, why fund an unpopular, messy, and downright dangerous technology (albeit one that actually works) when in a couple of decades (or maybe 3 or 4) we could have all the clean safe energy we want – and everyone would live happily ever after. All we had to do was get through “the energy gap” - the (now obsolete) phrase that referred to the time between fossil fuels running out and hot fusion coming on line. What ever happened to that? - Leo ps. Actually, they did offer me a job – but I turned it down, and instead went off to further my studies (although later returning to work at their sister site, the infamous Harwell – but that will be another tale ;-)
