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Major breakthrough on nuclear fusion energy

bbc.co.uk

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Re: Major breakthrough on nuclear fusion energy

#201

Post by arlort »

lisper wrote: post #163
reacharavindh wrote: post #107

As an uneducated observer to nuclear physics, I could not tell the significance of this achievement. Did we finally learn how to extract more energy from a fusion rector than we supplied to operate it? Could anyone more in the know here explain in simpler and more practical terms please?

> Did we finally learn how to extract more energy from a fusion rector than we supplied to operate it? No. > Could anyone more in the know here explain in simpler and more practical terms please? It's impossible to tell because the story is incoherent. The central claim is that they "release[d] a record 59 megajoules of sustained fusion energy" but this makes no sense. One can talk about sustained power (over a perio…

They expand under the article (not the clearest visual design though, I thought it was an ad or some "related" section)

The record is for energy generated. They generated the most energy, however they did not generate the most power (unlike the previous record which generated both the most energy and most power) because they were focusing on sustained generation

The sentence "59 megajoules of sustained fusion-energy", where fusion is the source of the energy, doesn't make sense

I think they meant it as "59 megajoules of sustained-fusion energy" where sustained fusion is the focus of the experiment (not sure I managed to get through what I meant and it's worded awfully on the website)

I hope / expect the actual paper/technical reports which will come out will be worded more clearly

Re: Major breakthrough on nuclear fusion energy

#202

Post by Yajirobe »

mattalex wrote: post #181
reacharavindh wrote: post #107

As an uneducated observer to nuclear physics, I could not tell the significance of this achievement. Did we finally learn how to extract more energy from a fusion rector than we supplied to operate it? Could anyone more in the know here explain in simpler and more practical terms please?

> Did we finally learn how to extract more energy from a fusion rector than we supplied to operate it? No. The issue is that most people only report the gain over the plasma (i.e. how much energy was put into generating the plasma) rather than the full amount of energy put into the process (i.e. superconductors, magnets, generating the deuterium/tritium, maintaining the sun-like heat, etc). If you add this to the com…

50x is not orders of magnitude off. It's one order of magnitude

Re: Major breakthrough on nuclear fusion energy

#203

Post by jopsen »

spuz wrote: post #6

> The experiments produced 59 megajoules of energy over five seconds (11 megawatts of power). > This is more than double what was achieved in similar tests back in 1997. > It's not a massive energy output - only enough to boil about 60 kettles' worth of water. But the significance is that it validates design choices that have been made for an even bigger fusion reactor now being constructed in France. I thought this…

When discussing nuclear power plants we can all debate aspects of the bikeshed.

When discussing fusion power, we can all debate how many kettles we can boil.

Kind of funny :)

Re: Major breakthrough on nuclear fusion energy

#205

Post by nosianu »

jvanderbot wrote: post #190
nosianu wrote: post #184

Earlier quoted context omitted.

Yeah, but that helped out a lot of US companies that have significant lobbying backing and districts where those companies are located. Similar to how some NASA things get funded. The outcome itself is not nearly enough, if it even matters (see Afghanistan, it' s not like the outcome was a surprise): What needs to happen is that the money river* needs to flow through areas that have influential congress(wo)men and se…

Well, it's not like the US would pay someone else to develop NASA's missions, would they? Part of the point of NASA is to keep aerospace expertise thriving, (I'd argue one of the primary goals, in fact), by answering really challenging science questions. You're right in letter, but off in spirit by comparing it to war profiteering. Just imagine where we'd be if the US had a similar "Focus here" initiative for semicon…

I would like to emphasize, since I did not already do so, that I make no value judgment. It is the public that does not want the US government to do "socialism", but there seems to be a real need for it so politicians do it through the back door. How well that works is another matter. It's not wrong for politicians to pay attention to try to keep jobs, or to keep certain industries alive for which there only is infrequent real need, which the short-term business management outlook would leave rotting.

I think independent of how well it works, or how terrible, to me it's an example of the "life finds a way" meme. Some great need exists, but also some great constraints, and a large amount of irrationality, so the outcome is what it is.

.

> Just imagine where we'd be if the US had a similar "Focus here" initiative for semiconductors since the 1960s.

You may want to buckle up and watch the excellent talk https://youtu.be/ZTC_RxWN_xo

> Today, Silicon Valley is known around the world as a fount of technology innovation and development fueled by private venture capital and peopled by fabled entrepreneurs. But it wasn't always so. Unbeknownst to even seasoned inhabitants, today's Silicon Valley had its start in government secrecy and wartime urgency.

> In this lecture, renowned serial entrepreneur Steve Blank presents how the roots of Silicon Valley sprang not from the later development of the silicon semiconductor but instead from the earlier technology duel over the skies of Germany and secret efforts around (and over) the Soviet Union. World War II, the Cold War and one Stanford professor set the stage for the creation and explosive growth of entrepreneurship in Silicon Valley. The world was forever changed when the Defense Department, CIA and the National Security Agency acted like today's venture capitalists funding this first wave of entrepreneurship.

Re: Major breakthrough on nuclear fusion energy

#206

Post by marginalia_nu »

mmazing wrote: post #195
marginalia_nu wrote: post #166

Earlier quoted context omitted.

Nothing concrete to add, just the anecdote that the plasma physics class I took in grad school hands down had some of the sketchiest looking physicist math I think I have ever seen. Felt like a SWAT team from the mathematics department might burst through the door at any time.

Like an ECON 101 course? I felt like the Calculus SWAT Team was going to burst through the doors in that class, ha.

This was no regular spherical cow, I tell you it was assumed to be time-independent while at the same time having an oscillatory frequency.

Re: Major breakthrough on nuclear fusion energy

#208

Post by lisper »

rat9988 wrote: post #193
lisper wrote: post #188

Earlier quoted context omitted.

> "59 megajoules of sustained fusion energy" means a single burst produced that much. In what sense is that "sustained"? A typical power plant produces that much energy in less than a second on a continuous (i.e. sustained) basis. Producing 59 megajoules once is basically a joke. It is analogous to detonating a pipe bomb (at a cost of several billion dollars) and claiming that as significant progress towards an inter…

> A typical power plant Fusion power plant aren't typical though

Yes, that is exactly the problem. If they are ever going to be commercially viable they need to become typical. 59MJ per cycle isn't going to do you a lot of good if a cycle time is measured in months as is currently the case. You have to get that cycle time down to fractions of a second at this energy level before you even have a chance at commercial viability. 59 MJ is a tiny amount of energy by the standards of commercial power generation.

Re: Major breakthrough on nuclear fusion energy

#209

Post by jfengel »

whimsicalism wrote: post #136
limaoscarjuliet wrote: post #109

According to Sabine Hossenfelder, published numbers are frequently mis-stated on purpose. When you look at frequently reported Q Plasma (or plasma efficiency) we are not that far from it being > 1. However, we should look at Q Total (total efficiency), which is still way below https://www.youtube.com/watch?v=LJ4W1g-6JiY For years, I was hoping fusion is close. After watching Sabine's video, I'm not so optimistic anym…

Sabine is overly critical IMO. The distinction she is making is known to anyone who has spent a little bit of time thinking about fusion (hopefully that includes the grant writers) and projects like ITER are explicitly aiming for Q=10, not just "breakeven"

That's kind of her thing. She is usually right, but also overly pessimistic in a way opposite from the popular press over-optimism.

I get frustrated because it paints science in an undeserved negative light. It is at least truthful, in a way that most anti science writing is not. Mostly I find it unhelpful in that it points out problems without either explaining why they were reasonable or giving a real alternative.

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