Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Successful second round of fusion experiments with Wendelstein 7-X

ipp.mpg.de

Post reply on HN
Print view View original

141–150 of 223 posts

Re: Successful second round of fusion experiments with Wendelstein 7-X

#141

Post by philwelch »

simonh wrote: post #133
ttul wrote: post #3

Experiments like Wendelstein remind me that the only thing holding back fusion power is money for research like this. Every year, we spend billions on fossil fuel exploration because the return on investment is quick - just think about all the wells going in to extract shale oil. What if we collectively had the will to invest this much into fusion?

>What if we collectively had the will to invest this much into fusion? If it were to turn out that fusion power isn’t technologically feasible within useful parameters (currently achievable technology, useful scales, economic feasibility of recovering the costs in the lifetime of a reactor, etc), we’d have squandered vast resources pointlessly. For a start there are dozens of different approaches currently being purs…

> If it were to turn out that fusion power isn’t technologically feasible within useful parameters (currently achievable technology, useful scales, economic feasibility of recovering the costs in the lifetime of a reactor, etc), we’d have squandered vast resources pointlessly.

Not necessarily, because discovering a large blocker would give us an idea of what to invest in next.

The economic impact of fusion power is great enough that even if there's a 10-25% probability of it working out, the expected value implied by that probability would justify significantly higher levels of funding than fusion currently receives.

> It’s not like fusion isn’t being actively investigated and invested in. It is, to the tune of tens of billions of dollars. How about we see how those projects pan out in practice and then progress from there?

ITER, the largest multinational fusion project, is projected to have a total cost of over 20 billion euros, which is about 22 billion USD. 22 billion USD is less than NASA's budget, adjusted for inflation, for the single years of 1963 through 1970 or 1990 through 1993. And NASA's work is built on top of the rocketry work of Nazi Germany, which cost about 40 billion inflation-adjusted dollars even with, to be euphemistic, artificially low labor costs.

For another point of comparison, the Persian Gulf War, which was primarily motivated by the attempt to secure part of the global supply of petroleum, cost $61 billion. The Iraq War cost at least an order of magnitude more, but (a) many of that was due to cost overruns and (b) that war was partially motivated by issues other than securing part of the world's petroleum supply.

In terms of improving long term human living conditions and enabling future economic growth, developing fusion power would provide tremendous benefits.

Re: Successful second round of fusion experiments with Wendelstein 7-X

#142

Post by sballin »

mpweiher wrote: post #93
gmueckl wrote: post #57

Earlier quoted context omitted.

Uhh... are you aware that the 7-X design was computed in the late 80s? It was just an enormous challenge to build this thing. Things like building and validating the field coils required a lot of effort and some novel approaches that they had to come up with along the way.

> 7-X design was computed in the late 80s? Source for that? Looking at the German Wikipedia entry, the HELIAS method was invented in the late 80s. I don't see anything about the 7-X design actually having been computed back then. In fact, even the 2002 experiment Wendelstein 7-AS wasn't fully optimised. Also, Tokamaks were invented in the 1950s. JET started operating in 1983. ITER was proposed in 1987. Given even jus…

Here's a source, unfortunately paywalled, from 1989: https://www.tandfonline.com/doi/abs/10.13182/FST90-A29178

I do research at W7-X, so I can confirm that to the best of my knowledge, the design was computed a long time ago. Building the actual device took a while.

Re: Successful second round of fusion experiments with Wendelstein 7-X

#143

Post by philwelch »

nine_k wrote: post #44
adrianN wrote: post #18

Earlier quoted context omitted.

Confining the plasma is easier in a larger reactor, so you might be better off building one big reactor instead of 20 small ones.

If confinement is easier in a large machine, why are not very large machines being built? If this is economically infeasible, then again, building piecemeal may be better, in the same way as taking a credit and paying interest on it might be better if you can't secure the upfront sum anyway.

This is kind of similar to how we use rockets instead of Lofstrom loops. The cost per kilowatt-hour of One Giant Fusion Reactor may be infinitestimal, but if you don't actually realize lower unit costs without a huge upfront investment, and there's no way to incrementally get some of the benefit for only some of the cost, it's a very hard sell.

Rockets are an easy sell because you can design a rocket that launches from Holland and lands on London and you can find someone to fund that. Later, based on that track record, you can design a rocket that launches from Florida and reaches low earth orbit, and you can find someone to fund that. After you pull that off, you can make a rocket that launches from Florida and reaches the moon, and you can find someone to find that based on your track record.

Conversely, if you wanted to build a Lofstrom loop, you would have to tell someone, "hey, there's no track record of something like this working, but give me tens of billions of dollars and you'll make it back by not blowing as much money on rockets". Nobody's gonna pay for that. And if you start building it piecemeal, you're still not going to get anything to space, and then people will point and laugh and talk about how Lofstrom loops are a stupid technology that will never work out because they're always another 20 years away, so you never get the necessary funding to actually finish the thing, which means people will just continue to point and laugh, and in allegorical form, this is the history of fusion power.

Re: Successful second round of fusion experiments with Wendelstein 7-X

#144

Post by jessriedel »

nine_k wrote: post #60
jessriedel wrote: post #53

Earlier quoted context omitted.

That would just record the total neutron flux. It won't form an image unless you have a lens, aperture, or something similar.

It's almost as if you posit that the flux through every piece of surface is exactly the same. I suspect it's not.

No, total flux at a given location, not total flux in the whole device. The point is that it doesn't identify which direction the neutrons are coming from. That's why lens or apertures are needed.

Re: Successful second round of fusion experiments with Wendelstein 7-X

#145

Post by sballin »

saganus wrote: post #5

Does anyone have any idea how do they take pictures of the plasma? That seems quite hard considering the temperatures and the strong magnetic field.

I operate a fast camera at W7-X. It's a normal high-speed camera that records light in the humanly visible range, and the plasma emits in that range and reflects off the walls. IR cameras are most often used to gauge the temperatures of vessel wall components.

Our camera looks through a pinhole in the vessel wall, but it sits a few meters away from the machine and gets that view through a bundle of optical fibers. There wouldn't be enough space to place the camera right at the pinhole because of the magnets and their cooling systems, and the magnetic fields would be pretty high. The camera needs to be shielded from the fields for its electronics to work properly, and the shielding box perturbs the magnets' field, so moving the camera far away is a good idea. We don't worry about neutrons, because W7-X plasmas are fueled with stable helium and hydrogen (no deuterium or tritium so far, mainly due to onerous nuclear regulations in Germany), and these fuels don't produce many neutrons at all.

Re: Successful second round of fusion experiments with Wendelstein 7-X

#146

Post by xxgreg »

sballin wrote: post #142
mpweiher wrote: post #93

Earlier quoted context omitted.

> 7-X design was computed in the late 80s? Source for that? Looking at the German Wikipedia entry, the HELIAS method was invented in the late 80s. I don't see anything about the 7-X design actually having been computed back then. In fact, even the 2002 experiment Wendelstein 7-AS wasn't fully optimised. Also, Tokamaks were invented in the 1950s. JET started operating in 1983. ITER was proposed in 1987. Given even jus…

Here's a source, unfortunately paywalled, from 1989: https://www.tandfonline.com/doi/abs/10.13182/FST90-A29178 I do research at W7-X, so I can confirm that to the best of my knowledge, the design was computed a long time ago. Building the actual device took a while.

Do you have any links to a high level description of how this would be hooked up to a powerplant? Would this be used to heat water as per a typical fission plant?

Re: Successful second round of fusion experiments with Wendelstein 7-X

#147

Post by DennisP »

petra wrote: post #124
ChuckMcM wrote: post #64

Earlier quoted context omitted.

It is odd that you mention this, unless your name is Karl and were at lunch last Wednesday :-), because it came up as something that companies with big cash hoards might actually be thinking about. Consider the notion that at some point a feasible fusion power plant design becomes "known". Then its a question of money to build one or two or 10. And a company like Google or Apple, with a large cash hoard could jump in…

Maybe for companies, to aim for fusion is asking too much. But what about a commercial "DARPA" ? I'm guessing that the innovations created by DARPA are a very good ROI in the value sense. If not, what is? But like Xerox-Parc, the fear is that extracting money from that won't go well. So one solution is creating a monopoly. But that's not ideal. But what about some sort of insurance ? How would history look if Xerox-P…

For some companies asking for fusion isn't too much. Fusion startups include (among others) Commonwealth, Tokamak Energy, General Fusion, Helion, and TAE (formerly Tri Alpha). The latter has over $500 million invested.

And for a company that's not a startup, Lockheed Martin has a fusion project.

Re: Successful second round of fusion experiments with Wendelstein 7-X

#148

Post by narrator »

lifeformed wrote: post #27
ttul wrote: post #3

Experiments like Wendelstein remind me that the only thing holding back fusion power is money for research like this. Every year, we spend billions on fossil fuel exploration because the return on investment is quick - just think about all the wells going in to extract shale oil. What if we collectively had the will to invest this much into fusion?

A company like Apple has a quarter trillion in cash laying around, they could jump start fusion and control near-limitless energy in several decades. I wish there was more of a visionary drive among institutions for intellectual curiosity and pushing the boundaries of humankind. And yes, I know why they don't... shareholders business plans risk blah blah blah. Reality is just so BORING. Maybe one day we'll find a way…

They have all that money because they make good investments. In the pursuit of fusion, a quarter trillion spent by Elon Musk goes a lot farther than a quarter trillion spent by a lottery winner. It's not just about how much money you have, but who you give it to and for what that determines its value. Just because we are used to indistinguishable standardized consumer products that cost X doesn't mean investing works that way, especially when the certainty of the venture is not assured and is partially the responsibility of the investor to make sure that the money is being directed properly.

Re: Successful second round of fusion experiments with Wendelstein 7-X

#149

Post by gmueckl »

mpweiher wrote: post #93
gmueckl wrote: post #57

Earlier quoted context omitted.

Uhh... are you aware that the 7-X design was computed in the late 80s? It was just an enormous challenge to build this thing. Things like building and validating the field coils required a lot of effort and some novel approaches that they had to come up with along the way.

> 7-X design was computed in the late 80s? Source for that? Looking at the German Wikipedia entry, the HELIAS method was invented in the late 80s. I don't see anything about the 7-X design actually having been computed back then. In fact, even the 2002 experiment Wendelstein 7-AS wasn't fully optimised. Also, Tokamaks were invented in the 1950s. JET started operating in 1983. ITER was proposed in 1987. Given even jus…

https://aip.scitation.org/doi/10.1063/1.860481

This paper published in 92 mentions that the 7-X was being designex at that time. I remember having seen images of the proposed field coil configuration in 91 or 92. So I might have bern off by a few years. But the plans must have bern complete for the project start in 1994.

Re: Successful second round of fusion experiments with Wendelstein 7-X

#150

Post by Retric »

saagarjha wrote: post #116
Retric wrote: post #43

Earlier quoted context omitted.

> Maby we could still Early computers where huge and broke down all the time. They where built that way because it was the easiest option at the time. Nobody wants to build multi billion dollar devices if you could get away with spending 1/10th as much or even test several designs at the same time they would. PS: The grid absorbs solar and wind interment nature just fine without much in the way of storage. That might…

> The grid absorbs solar and wind interment nature just fine without much in the way of storage. I was under the impression that this was because we have a bunch of natural-gas power plants that are turned on when necessary to meet peak load.

This is regional, the general factors are over supply is required to deal with failures. So, their should always be excess capacity which can be routed around at 1/3 the speed of light. Demand can be adjusted in response to increased prices. Relatively tiny amounts of storage allow for time to react.

Large scale hydro for example can act as storage ramping up and down in minutes to cover demand spikes.

PS: Sure in the US it’s a lot of cheap natural gas right now. But many places don’t and still need to deal with the same issues.

Post reply on HN