Not poll...what about fusion?

Another not-poll, since these have gone so well. :stuck_out_tongue: Anyway, same parameters as the last 2, which to recap for the majority who probably never saw the other not-polls, what time frame do you think we are talking about for fusion? And by that I mean a working prototype of a fusion reactor that could be commercially built (could means is possible, not that it’s necessarily commercially feasible)? In your life time? In the life time of someone alive today? A few generations from then? Never? 30 years from now, with ‘now’ being an ever moving target? What are your opinions on this one?

Every year since I was old enough to notice it, there seems to be a yearly “fusion breakthrough” announcement in media sites that aren’t completely off their rocker. And each time making statements like “commercial fusion power generation is just around the corner!” That’s over 5 decades of false hopes, and counting.

Oh, I expect they’ll get it eventually. But I’d not be surprised if it’s still a century away. I would be surprised if it was sooner than 25 years, however. I don’t expect to see it in my lifetime.

At least 25 years. That’s the limit of our future vision, and it’s past that. We could get some kind of breakthrough any day now that will draw us closer but a working prototype that might be commercially feasible will be at least 25 years away even if it happens tomorrow.

The only way it happens sooner is an advance in science that shows us fusion is much easier achieve than we know now.

Here is an interesting advance: some researchers experimented with turning a tokamak inside out and got some promising results.

The toroidal plasma ring in a tokamak has a profile that is vertical on the inner side and curves around the outside – sort of a “D-shaped” cross-section. The experiment turned the “D” around, so that the curve faces the inside and the outside is more vertical. The plasma performed much better, even in a chamber that was designed for the opposite profile. So, maybe, in just 20 years, they will have this working.

Well, my thoughts are, unsurprisingly, going to buck the trend. I actually think we are getting closer. I expect a working prototype within 10 years. I SHOULD live that long. :stuck_out_tongue: There are a number of efforts underway around the world on this and some serious money being put into them…and a number of different strategies being tried. Yeah, I agree they have promised that it was right around the corner for decades now…really, all my life I’ve heard some version of it’s 10/20/30 years away…but I actually think they are close. I think we’ll know if some of these teams are going to have something that pans out in less than 10 years. IIRC, the one in Europe is only a few years from being able to start testing. And there is a promising team in the US and China as well as a few others.

Now, how long until whatever they come up with is able to be put into production? THAT I think will be beyond my lifetime. But a working prototype that produces more energy than it uses and COULD be produced? I think we are relatively close to that.

The ITER experimental reactor is supposed to be fully operational by 2035 and is actually being assembled, not a sci-fi story or hole in the ground. The prototype commercial reactor to follow is still only in the concept stage, though (thus still “30 years from now” before it starts producing power).

I expect industrial civilization to permanently collapse within a few decades, before commercially viable fusion is achieved. So, “never”.

The real question is whether it will be practicable. We may be able to reach real, workable positive output, but will the exotic hardware be able to survive years of intense radiation? If we can do fusion but have to be replacing the expensive lanthanide magnets every year, at high cost, will it end up actually being net positive output?

Yeah, that’s true and it might be the case. I was really just asking about a fusion prototype that produces more energy than it uses to start the reaction, but commercial and actually deployed fusion? I don’t think that will happen in my lifetime, or perhaps in the lifetimes of someone alive today, but I could be wrong. We could make a number of breakthroughs tomorrow or next year with all the teams looking into it.

I have no idea. Like QtM it seems to be one of those ‘just around the corner’ technologies and I have no idea how many more bottlenecks have to be fixed before it becomes viable.

Personally I’m going to assume that affordable rooftop solar and cheap battery technology will become feasible before fusion power does, which will eliminate a lot of the demand for it since rooftop solar won’t require a grid. However I have no idea how rooftop solar will meet the demands of heavy industry so maybe there will be a place for grid electricity.

As an uneducated guess, ~20 years before a stable fusion prototype, then another 10-15 years before an industrial scale one is released.

I suspect a large part of the problem is the hill research has to climb – not the technical hill but that of support and funding. Consider the Mirror Fusion Test Facility at LLNL: they spent years and $372M building it, and the day after it was completed, the Reagan administration mothballed it, let the huge edifice sit idle for a year and finally cancelled the project. (It sounds like CT, but it is well known that Reagan, et al, were very much in bed with big oil, which has never been very enthusiastic about nuclear power, make of that what you will.)

Our need for heavy industry may be a bit exaggerated, IMHO. I see a huge fraction of our tangible output going into the landfill very quickly. Our economy demands high throughput, which may well represent a large energy source, in the form of not producing such a ridiculous amount of waste ITFP.

According to the documentary film Back to the Future, we were supposed to have commercially available fusion reactors four years ago.

Do you mean the follow up documentary? Because I think the first one only explored 1955.

I think I happen across some news about ITER every few years. Based on that, I’d say that we’re still probably (at least) two generations of design away and given that these sorts of projects can take 20-30 years to construct, that puts us 40-60 years out still.

If it weren’t for the difficulty of building the things, we’d probably be there already (presuming that it’s actually possible to do). But it’s hard to develop something when your REPL cycle is in the decades.

Fusion power is 30 years away. It’s always 30 years away. 20 years ago, it was 30 years away. 20 years from now it will be 30 years away.

When they get a reactor going that produces more power than it consumes and can run for hours or days, then it probably will be 30 years away. Until then, it’s always 30 years away.

I don’t expect to see it in my lifetime.

I suspect this is the answer. Sometimes incremental improvement in technology that already works is a better bet than breakthrough improvement in remarkable new technology.

No, I think Mr. Fusion appeared at the end of the first one when he comes back to get Marty. Remember, he doesn’t need roads.

The problem is that fusion is simple in concept but fiendishly difficult in practice, and the more we learn about the necessary conditions to initiate and maintain over unity nuclear fusion, the more difficult it appears to achieve plasma confinement to breakeven conditions. ITER is about a decade behind schedule now and there are still some fundamental issues to achieve the desired Q=10 yield that are not resolved.

The other thing to bear in mind is just achieving equilibrium and target energy yield is only the first step toward commercialization. Because D-T fusion produces an alpha particle and high energy neutron, the output has to be thermalized to be able to do work, and that may prove to be just as difficult as achieving fusion. There is also the issue that energetic neutrons will weaken (embrittle) material, so some kind of protection is required. Some proposals actually use a blanket of fissionable or fertile materials to breed fuel for nuclear fission reactors but the mechanics of how that would work are undefined, particularly since it would involve handling highly radioactive materials which would then have to be processed into fuel. There are “alternative” methods which have been suggested for fusion power like that being developed by Commonwealth Fusion Systems, General Fusion, or Helion, but thus far none have even demonstrated proof of concept, and while there is a growing consensus that there is ‘something’ going on with low energy nuclear reactions (LENR) it is unclear whether it can deliver enough power throughput to be a useful source of electrical power generation.

Principles of Fusion Energy covers the essentials of nuclear fusion power; although published in 2000 it is still more or less up to date, and while it is intended as an introductory textbook for engineers you can skip past the equations and get the gist of the issues, especially if you have taken basic classical electrodynamics.

Stranger

Quite right. Remember when Doctor Brown was rummaging through the garbage can for the necessary fuel?

30 years ago, it was only a few years away. A few years after that, it was 30 years away again. Cold Fusion fail.

30 years and 3 days ago, to be exact.