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Could a Helium-Resistant Material Usher In an Age of Nuclear Fusion? (sciencealert.com)
Researchers working with a team at the Los Alamos National Lab tested a new way to build material for nuclear fusion reactors, "and found that it could eliminate one of the obstacles preventing humanity from harnessing the power of fusion energy." schwit1 quotes Science Alert:
A collaboration of engineers and researchers has found a way to prevent helium, a byproduct of the fusion reaction, from weakening nuclear fusion reactors. The secret is in building the reactors using nanocomposite solids that create channels through which the helium can escape... Not only does the fusion process expose reactors to extreme pressure and temperatures, helium -- the byproduct of fusion between hydrogen atoms -- adds to the strain placed on reactors by bubbling out into the materials and eventually weakening them...
In a study published in the journal Science Advances, the researchers overview how they tested the behavior of helium in nanocomposite solids, materials made from thick metal layer stacks. They found that the helium didn't form bubbles in these nanocomposite solids like it did in traditionally used materials. Instead, it formed long, vein-like tunnels. "We were blown away by what we saw," said Demkowicz. "As you put more and more helium inside these nanocomposites, rather than destroying the material, the veins actually start to interconnect, resulting in kind of a vascular system."
The article points out that nuclear fusion generates four times the energy of nuclear fission.
In a study published in the journal Science Advances, the researchers overview how they tested the behavior of helium in nanocomposite solids, materials made from thick metal layer stacks. They found that the helium didn't form bubbles in these nanocomposite solids like it did in traditionally used materials. Instead, it formed long, vein-like tunnels. "We were blown away by what we saw," said Demkowicz. "As you put more and more helium inside these nanocomposites, rather than destroying the material, the veins actually start to interconnect, resulting in kind of a vascular system."
The article points out that nuclear fusion generates four times the energy of nuclear fission.
This is an interesting development in materials science, but helium diffusion weakening of containment vessels is pretty far down the list of critical problems standing in the way of producing commercial energy from fusion any time this century.
The key obstacle, even more important than the fact that no power producing fusion reactors have yet been built, nor are likely to be in the next 30 years, is that they will not be able to compete with other sources of electricity. Fusion power is going to be much more capital intensive than fission power plants that already have trouble competing with other sources of electricity due to their construction costs. No new material for a container wall is going to fix this.
Starships were meant to fly, Hands up and touch the sky - Nicky Minaj
Sure you can. That is what E=mc^2 means. You can convert mass into energy.
I’m been hearing fusion is only 20 years away for at least 30 years now.
It is worse than that. The time until we get fusion power is a monotonically increasing function of calendar year. In the early 1950s, when Project Sherwood was started, it was highly classified because it was thought that it would produce fusion power so soon (i.e. less than a decade) that it would be a valuable military technology. By the late 1960s they were talking about it being achieved in 20 years. By 2000 the timeline had grown to 30+ years.
In 2014 the projection for DEMO, the ITER follow-on, which is described as a system that would bring us to the "threshold of a prototype fusion reactor", i.e. short of being an actual prototype fusion power reactor, which in turn is short of being an actual commercial power reactor, was projected to start operating in the 2040s, i.e. at least 30 years, if no further schedule slippages occur. Currently, PROTO, the actual prototype fusion power reactor is not envisioned before the 2050s and likely later, which brings us about 40 years, and we still aren't talking about an actual commercial power plant. Allowing for the established 20 year cycle for each iteration of a major fusion reactor project, we might get that commercial power plant in 60 years. But it will be too expensive to compete with other sources of power.
Is some other new fusion design going suddenly break us out of this pattern? There is no law of nature against it, so it is possible. But literally hundreds of fusion schemes have been investigated, and without exception every concept has proven much harder in practice than on paper (or computer). Engineering by press release does not cut it (Lockheed Martin I am looking at you), until an actual demonstration unit is operating with predicted performance all claims on new breakthroughs should be ignored.
Starships were meant to fly, Hands up and touch the sky - Nicky Minaj
> helium -- the byproduct of fusion between hydrogen atoms -- adds to the strain placed on reactors by
> bubbling out into the materials and eventually weakening them
The problem with fusion is that it generates relativistic neutrons that displace atoms in metals and cause them to become brittle. This not only weakens the materials but makes some critical materials like the superconducting magnets rapidly turn into scrap.
While the helium -alphas actually- also present problems, they are not the same thing at all. The damage rate from such events is orders of magnitude lower than the neutron damage. And the idea that letting them just bubble out will remove them from the fuel at a fast enough rate makes me LOL.
The idea that this somehow fixes anything is so utterly ridiculous that it simply puts the black hole that is modern fusion research into stark perspective.
Here's why. The projections in 1976 seem to have been overly optimistic regarding our minimum commitment to research, but possibly overly pessimistic regarding our ability to perform in the worse-than-worst-case scenario.
https://www.google.ca/url?sa=i...
Fossil fuel plants, other plants that burn material, nuclear fission plants, and the proposed fusion plants all take water, heat it up so that it's a vapour, and run it through turbines. In some places the use the remaining energy to heat buildings and heat water. But for the most part it's so inefficient to boil water just to let the vapour turn a turbine. What we really need is to find a better way to turn the heat from these sources into electricity.
That doesn't make sense. Why?
Technically you are liberating the energy not creating it but even a fool can be right .
So OSX?
The nuclear fusion community talking about helium diffusion in reactor walls is kinda like the space travelling community talking about the lack of clear sun hours in Martian wellness resorts.
Is some other new fusion design going suddenly break us out of this pattern?
I think so. These magnetic confinement designs have a toroid shape to the plasma, making the volume of plasma needed for breakeven much larger than if it was a sphere. Spherical containment using a magnetic field is not likely possible. What would be possible for spherical containment is an electrostatic force. There's been some research in this funded by the US Navy but they've always been very secretive and underfunded because the Navy suspects that if the project got too large then it'd be taken over by the Department of Energy and killed, as it competes with their magnetic confinement projects.
Another interesting confinement is to use a magnetic field but on a molten metal, the fusion fuel is contained in this molten metal "bottle". By using powerful rams to move the metal inward the fuel is compressed inside this collapsing bottle. The heat and pressure would, theoretically at least, fuse portions of the fuel and keep the metal hot. Repeated ramming would keep fusing the fuel and the excess heat is extracted to produce power.
These are far less expensive experiments in fusion compared to the tokamak designs that so many people (or nations rather, I don't think the people have much say on this) are dumping money into. I believe these other designs are also far more likely to be energy positive at a reasonable scale. Any fusion project can be energy positive if scaled large enough, we have ample evidence of that in the universe. The reason the US Navy is funding their own fusion project is that they believe it can be used to power a future aircraft carrier or submarine. I suspect that they will not find that feasible, but even then they must see value in this as a source of energy for military strategic reasons.
I recall reading some articles on these alternative fusion reactor designs and it was something like the power input required grew on the square of the diameter but the power output grew by the cube. Their early experiments required X watts of power in, gave Y watts of power out for a given diameter Z. For X to be larger than Y meant Z had to be, again as I recall, much larger than the size of a typical fission reactor. For this to be practical means the capital expense would be much larger than any fission project attempted so far. Who is going to spend that kind of money when fission is already a proven technology?
One thing that determines the size of the reactor is the fuel. Some fuels are better than others and, of course, the best fuels are rare and expensive. If we are going to use a lower quality fuel then the size increases even more.
What's going to break us out of this pattern of fusion always being 30 years in the future is the Department of Energy getting off the idea that magnetic fusion is the only path to take. They need to get serious on this and invest in, or at least issue licenses for, competing fusion technologies. If these competing technologies actually prove successful though then the Department of Energy would look really stupid for investing so much money into something that didn't work AND they'd actually solve the problem that they were set to solve, therefore making the future existence of the department unnecessary.
The Department of Energy isn't going to solve our energy problems because it would not be in their best interests to do so. So long as energy scarcity is a problem they have a mission. I say dissolve the Department of Energy and roll over much of its people, assets, and mission into the Department of Defense. What does not fit into the likes of energy development, nuclear weapons, research, and such, can be rolled into the Department of Commerce or some other government entity. The Department of Energy needs to go away. If we can't make it go away then we should put people in charge that are actually motivated to have the department pursue it's mission.
I am armed because I am free. I am free because I am armed.
Before you start worrying about the walls of your fusion machine, you need a fusion machine that can provide net positive energy.
Excuse me, but the point of this article is that the walls are part of the fusion machine.
When all you have is a hammer, every problem starts to look like a thumb.
There will never be a "Year of Linux on the desktop" because the desktop is dying.
That doesn't make any sense at all. First, you are confused about the term "desktop"... it means a particular kind of GUI, not the form factor of the machine. The desktop will never will never die because it is the most productive interface for people who actually need to do desktop kinds of work. So, at the moment, many people use a desktop for something else entirely, e.g., consuming media. Those will migrate away, but have you ever tried to write an essay on a phone? You can do it, but it's painful. You don't want to do a whole hell of a lot of software development on a phone either. So there always will be a core constituency of desktop users, even if diminished from today's numbers. With the desktop shrinking, and Linux's absolute numbers of desktop users growing, the net effect is to hasten the day when Linux desktop usage increases beyond a sliver of the pie chart, exactly the opposite of the result you suggest. Meanwhile... writing this on a Linux desktop and liking it.
When all you have is a hammer, every problem starts to look like a thumb.
Oh god not this chart again. Anyone that posts this is demonstrating that they are unfamiliar with the history and physics of fusion. So let's explore this...
Right when the entire concept was starting in the 1940s, there was a theoretical calculation that estimated how quickly the plasma would leak out of the machines. Among the various inputs were two that were key - the plasma leaked slower out of larger machines because it had further to go, so that was linear with size, and in addition, the scattering varied with the square of the magnetic field strength so if you made the magnets even a little stronger then you're good to go.
However, there was one problem. During the war, they had actually worked with magnetically confined plasmas as part of the bomb project. The actual measured results from these experiments were WAY faster than what the classical math predicted. Most worryingly, the magnetic field only improved the times linearly. If this "Bohm diffusion" was correct, there was no hope of making a working reactor.
So when they built the first machines and ran the calculations, it appeared the classical numbers were working. If they just made it bigger they would be off to the races. So through the late 1950s and into the 60s they did that. And sure enough, the results got worse. At a 1968 meeting, Spitzer, the dean of the US program, had a chart showing that the entire stellarator series was clearly following the Bohm model.
Fusion was dead.
Funny thing though... at that same meeting the Soviets showed the results of their new tokamaks and they were 10x Bohm. The results were so good, no one believed them. They had to invite a team from the UK to use their laser scattering probe before anyone was convinced it actually worked.
And then there was a sudden rush to build tokamaks. So much of a rush that they converted the biggest stellarator into one and never looked back. Now the problem was not stability, it was heating the fuel - previous machines like the pinch series heated the fuel by either compressing it rapidly or running a current through it. The tokamak showed that there were hard limits on both, and these were too low to use for heating.
So through the 1970s you had a series of experiments all around the world on how to heat the fuel. Generally, the US was the winner. The PPPL's PLT machine was able to hold its plasma and heat it until it reached the conditions for fusion. All that was left was to increase the pressure to a useful figure, and then introduce tritium so the thing would actually burn.
And that's where this graph comes in. Notice the start point of this graph, in the mid-1970s. This is when Hirsch was putting together the Manhattan Project-level attempt to make a working commercial machine around 2000. Based on this there were going to be three machines in a rapid sequence, first the follow-on to the PLT, which became TFTR, then a prototype generator that also handled tritium production, and then the prototype commercial machine. That's the green line in the chart.
What actually happened is that they built TFTR and it didn't work. As they ramped up the dials, the machine became increasingly unstable. By around 1983 TFTR failed, MFTF never even turned on, and congress, realizing no one really knew what the hell was going on, cut the funding.
So basically the green line is based on the underlying premise that they actually understood the physics. But they didn't. And if you don't understand the physics, it doesn't matter how much money you pour into it, it still won't work. So the black line happened.
In spite of this, fusion proponents keep putting this up and blaming money for "the problem". THIS IS A PHYSICS PROBLEM, IT'S NOT A MONEY PROBLEM. And we still don't really know the solution, and a trillion dollars won't fix that.
Makes no sense. Fission ~ 200 mega-electron-volts/per, fusion ~ 16 mega-electron-volts per.
Maybe per gram?
See my handle. Guess what I do all day?
While some here talk about "many approaches have been tested" it's really not true - the huge majority - way over 90% - of the money is tokomak, the others can go pound sand, which means only the dedicated and independently wealthy can work with them. As mentioned elsewhere, no matter the approach, this isn't what is holding fusion back. Nor is it necessarily more capex - till we have it making gain, we don't know which approach works and therefore don't have a clue about costs. Making assumptions often makes you wrong.
I saw this paper in the puff-sheet science news. It's the usual "I found something the sources of funding might be bullshitted about so give me more money" that we see all day every day in just about every field. Most of us know to ignore that junk.
Why guess when you can know? Measure!
"and congress, realizing no one really knew what the hell was going on, cut the funding."
Well gee, there's your problem. In science, if you don't understand a problem, you generally invest -more- time and energy into figuring out what the hell is going on.
You seem a little bit confused about the technology and the science behind it.
There is no difficulty in using fusion to generate more electricity than you put in. That is actually easy.
The reactors being built aren't designed to do that. They're designed to be useful to the engineers figuring out how to build all the parts to be durable and find out exactly which configurations give the best efficiency.
The reason it would not yet be cost effective isn't about net energy, it is about net money; making it last long enough to turn a profit! There are huge capital costs involved in construction.
Long post. Not much relevant until the end. When nobody knows what's going on, you require scientists to do research to figure out what's going on. That requires money. No money, you continue not knowing what's going on.
Slashdot user Maury Markowitz apparently think's commercial fusion is impossible, and impossible because physics. Cool. That's now part of the Internet record, so we can see if you were right. There seem to be a few thousand actual physicists who think there's a worthwhile chance you're wrong.
I think Maury may have some background in fusion research. If not, I do, at least.
The problem is not just money. It's also what the money is being used for: what kind of reactors are being built, what metrics are the government program managers are being sold on, what kinds of scientists are you employing, etc. There is a very big distinction between trying to solve engineering problems and physics problems.
ITER, and other reactor designs solve engineering problems, and try to answer the question "can we build a reactor with these specific plasma properties?" The physics questions are a lot more open ended, and any physics project has a much higher chance of failure than an engineering project.
I said I have some background in fusion. I worked on DIII-D which is a large fusion reactor run by General Atomics. Back then, I was probably best described as a computational physicist, now I'm a condensed matter physicist. I got into condensed matter physics because of my work on DIII-D. There were a lot of fusion scientists about 30 years ago who argued strenuously against building bigger and more expensive reactors. Instead, they argued we needed to focus on developing better components for the reactor designs we already have. That idea became IFMIF - a facility to test materials for fusion reactor use (fusion science likes these monolithic large projects - easier to fund, but they are SLOW). ITER was made the funding and marketing priority over IFMIF. Now, we're into engineering design on the system after ITER (DEMO), which requires input from IFMIF... which is still not built. So once again, we will go build an incredibly expensive reactor while using materials we know will not work in a commercial system because we're not willing to prioritize solving the physics problems. So, we can go on like this building reactors for a very long time without making real progress, and spend a lot of money along the way.
This Helium bubble stuff is interesting, but it's not a driving consideration. This is the kind of small project they've thrown to the materials folks to keep enough people involved until IFMIF is built.
> When nobody knows what's going on, you require scientists to do research
Exactly, you need *scientists* to do *research*, not *enginners* to build prototypes.
I thought I made that clear. I suspect it was to everyone else.
> and impossible because physics :rolleyes:
Thank you for demonstrating you can't be bothered to read anything that's "long", as my arguments are *very* clearly based on economics, not physics.
> ITER was made the funding and marketing priority over IFMIF
Which is precisely what that graph is as well - prioritizing an engineering prototype over the machines people actually needed.
One can't blame Hirsch - he felt there was a very real possibility that funding sources would dry up if they didn't demonstrate ignition soonish. And that's precisely how it played out in the end.
What the fuck is wrong with moderation on Slashdot?
The root premise is that the people who are best qualified to moderate and comment can only do one or the other, but not both, in any given conversation. This is a problem inherent to the mod point lottery system, and the score cap. If you're going to have a score cap instead of letting "everyone" score comments up and down, you're going to have to have this. And if you aren't, then you have to get a lot more serious about verifying your user base, which is why so many sites are using social media accounts for logins. It's a lot easier to let someone else police that.
I don't know of a third way to solve this problem, but on the balance, I much prefer this to being forced to use a social media login. It is quite a pisser, though.
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
> However... a tiny, tiny, tiny, tiny pittance of that energy is directed towards us at any one time
So? The question isn't the absolute number, the question is that number relative to actual usage.
According to the IEA, the Earth's total consumption is 132,000 terawatt-hours per year.
The amount of sunlight hitting the Earth is 174 petawatts, of which we can make practical use of about 1/2 (due to reflection, re-emission, and wavelength issues). There are 365 x 24 = 8760 hours in a year, so that's 174000 x 8760 / 2 = 762,120,000 TWh of solar energy per year.
So to power everything, we would need to capture 0.000173 of that energy.
> We then have relatively expensive devices utilising relatively unusual materials
Solar panels are the cheapest form of power in CAPEX terms in history:
https://www.lazard.com/media/438038/levelized-cost-of-energy-v100.pdf
By weight, they consist almost entirely of sand, with small amounts of aluminium, copper, silver and PET.
> So just stop faffing about, and recreate its energy source here on Earth
Given that you clearly don't know the first thing about modern PV, maybe you should stop "faffing about" and actually read a book or something?
There is no dark side of the Moon.
Your turn.
I'd say there's always a dark side of the moon. It's just not always the same side. And on those occasions when it passes into Earth's umbra then it's dark all over.