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French ITER Fusion Project To Take At Least 6 Years Longer Than Planned (sciencemag.org)
sciencehabit writes: The multibillion dollar ITER fusion project under construction in France will take at least an additional 6 years to complete, compared with the current schedule, a meeting of the governing council was told this week. ITER management has also asked the seven international partners which are backing the project for additional funding to finish the job. Under recent estimates, ITER was expected to cost some $13 billion and not begin operations until 2019. The new start date would be 2025.
There is an interesting talk on TED by the guy who started general fusion. Basically he shows a graph of the progress towards over unity production from commercial reactor designs since the 1950s. The progress has actually been surprisingly good, but the trouble is it has had to come from a long way back. If you consider that there is no fundamental law that makes the over-unity line special, it does seem like we are very close to crossing it now.
I think the biggest question though is whether these reactors will ever make commercial sense. The big benefit of fusion is that it has basically zero fuel costs and the potential to provide endless amounts of energy. But this is basically the same as renewables for all intents and purposes*. In the end it will really be a competition of capital costs, and given how simple something like a solar panel is, it may require an even bigger breakthrough beyond just getting a commercial reactor going to make fusion viable. Of course if they can get the size of the reactor down then that will open up huge opportunities as a high density power source (ships, aircraft, spacecraft), but again, that is going to need big breakthroughs beyond just achieving over-unity.
*while fusion has the potential to provide more energy than harvestable insolation, this would represent a massive injection of heat into the biosphere and I doubt that would have good implications for climate change. It is also hard to imagine what we could possibly do with that much energy without causing serious issues.
That's all well and good, but it doesn't actaully invalidate the "fusion power still 30 years away" comments. There may well be good reasons for the slow pace of development (I'd assume that was the case anyway), but that doesn't change the fact of it. Fusion power was supposed to be a few decades away when I was a kid, and it is still decades away (even if ITER does get turned on in 2025, and achieves its objectives, which will take a few years, it's just a research reactor, there will be more years of work before there is a functioning commercial fusion reactor).
> why did early attempts at production of fusion power fail to work out
Largely due to unrealistic assumptions on the part of the researchers involved.
Are you familiar with the Lawson criterion? Probably. Are you familiar with WHY he wrote it? Probably not.
He wrote it because he was tired of seeing everyone in the field making utterly ridiculous estimates about performance. There are countless experiments where basic math suggested the system would not work, but they went ahead and built it anyway without bothering to check first. Google "astron". There was so much belief in the ultimate success that no one listened when someone said there were issues.
And that's in spite of one of those people being Teller himself. In 1953 he gave an impromptu talk about stability in magnetic confinement and how he felt that it was a *very* difficult problem and no one was really thinking about it seriously. So, of course, everyone went off and thought about it seriously, right? No, they went off and wrote hand-waving statements about why their particular machine didn't apply, which then failed in precisely the way he predicted.
Lawson was equally tired of this. He sat down to put real numbers to the problem. He started by considering the power input and outputs needed to have the reactor produce net energy, and then worked to find the conditions needed to make that happen. His paper, which you can read here:
https://www.euro-fusion.org/wpcms/wp-content/uploads/2012/10/dec05-aere-gpr1807.pdf
(and it's very easy to read, so go ahead and do it) concludes "Even with the most optimistic possible assumptions it is evident that the conditions for the operation of a useful thermonuclear reactor are very severe". In case you don't recognize it, that's British humor: he's saying its almost impossible and everyone needs to stop and think seriously.
So, of course, no one did. They simply waved their hands some more and came up with reasons why they could reach these numbers, and the money kept coming. And coming, and coming. We're *sixty years later* now, Lawson has been dead almost a decade, and we're still trying. In that time we invented the IC, the internet, went to the moon, etc. At what point do you realize no one cares any more? Nuclear cars seemed like a good idea at one time too.
Enough already! The power companies have said they're not interested, how much money do we have to spend to change that?