Could Spacecraft of the Future Be Powered By 'Lattice Confinement' Nuclear Fusion? (ieee.org) 62
schwit1 writes: Researchers at NASA's Glenn Research Center have now demonstrated a method of inducing nuclear fusion without building a massive stellarator or tokamak. In fact, all they needed was a bit of metal, some hydrogen, and an electron accelerator.
The team believes that their method, called lattice confinement fusion, could be a potential new power source for deep space missions. They have published their results in two papers in Physical Review C...
"What we did was not cold fusion," says Lawrence Forsley, a senior lead experimental physicist for the project. Cold fusion, the idea that fusion can occur at relatively low energies in room-temperature materials, is viewed with skepticism by the vast majority of physicists. Forsley stresses this is hot fusion, but "We've come up with a new way of driving it."
The article contains a good description of the technical details, and end by summarizing the hopes of the project's analytical physicist and nuclear diagnostics lead. "This method of fusion offers a potentially reliable source for craft operating in places where solar panels may not be useable, for example.
"And of course, what works in space could be used on Earth."
The team believes that their method, called lattice confinement fusion, could be a potential new power source for deep space missions. They have published their results in two papers in Physical Review C...
"What we did was not cold fusion," says Lawrence Forsley, a senior lead experimental physicist for the project. Cold fusion, the idea that fusion can occur at relatively low energies in room-temperature materials, is viewed with skepticism by the vast majority of physicists. Forsley stresses this is hot fusion, but "We've come up with a new way of driving it."
The article contains a good description of the technical details, and end by summarizing the hopes of the project's analytical physicist and nuclear diagnostics lead. "This method of fusion offers a potentially reliable source for craft operating in places where solar panels may not be useable, for example.
"And of course, what works in space could be used on Earth."
Check the trash (Score:1)
Re: (Score:2)
I'm sure this new fusion technology will have an energy-positive working prototype just 20 years from now.
Re: (Score:2)
It is already net energy positive, so what is your point?
Re: (Score:2)
Man, if we could use PowerPoint slides as a power source, we could run the world on the marketing department. We've had fusion reactors that were great on paper for 50+ years now, and many prototypes that demonstrated the concept in practice, only they took more energy to power the prototype than it generated. Minor detail. Simple matter of engineering. In 20 years or so, fusion will be the only power source we need. This time for sure!
ITER is well along the way, and might shatter my cynicism in a few
Re: (Score:2)
Well, that "20 years in the future" is not what the actual scientists in the projects say. From a lengthy interview with the Wendelstein X-7 people, it sounds much more like 50 years or more, in particular because they have to invent devices, techniques and materials that are simply not available and they sometimes have to wait for other developments. For example, the design of their coils required some major advances in computer technology, because they could not have been designed before. The thing is tha
Re: (Score:2)
I doubt we ever will have "practical" fusion on earth.
Perhaps for space ships, but on earth we have the garbage and decommissioning problem, and wind and solar is simply more practical.
Re: (Score:2)
I'm fairly sure we'll get working fusion within a few decades given the right incentive or the right person to pick up the project. An incentive might be war, a person might be a Musk-type with a penchant for this field. Throw a few billion € at it in the right way - i.e. not through a committee which needs to satisfy half the world's politicians by doling out small parts to their constituencies - and we'll have fusion. I don't think it will end up being a massive project like NIF, ITAR or something of
Re: (Score:2)
Kalkar did not fail, it got canceled.
I'm pretty sure/convinced there will never be "practical" fusion on the planet.
Neither magnetic confined not electric confined fusion.
Bottom line it is just to complex to be more than a research topic (important imho, but not money wise ever giving a result).
Re: (Score:2)
I doubt we ever will have "practical" fusion on earth.
Perhaps for space ships, but on earth we have the garbage and decommissioning problem, and wind and solar is simply more practical.
Not really. Garbage for Fusion is pretty benign, you can basically let it sit for few weeks or so and it is gone. (48h half-life time on the main radioctives generated.) Decommissioning is unclear at this time, because the main final wall-cladding material is unknown yet. But again, this would be material that got irradiated by the fusion process and hence is very likely not to be a major issue.
That said, it really depends. Storage for wind and solar may be cheaper or not in the end. The most likely scenari
Re: (Score:2)
Not really. Garbage for Fusion is pretty benign,
No it is not.
The neutron flux converts everything around you into radioactive waste on the same level as a fission plant.
Neither for Solar (it will get recycled) nor for wind (which probably will be recycled soon as well), you need "radioactive proof" storage.
Re: (Score:2)
The thing is that we will at the very least learn a lot about plasma physics and materials and will get some useful other tech and devices out of it.
Oh, likely so. Far more practical than the LHC, and even that had some practical offshoots.
What is pretty much a certainty though is that all practical and scalable fusion tech will be much to late to do anything about global warming.
Well, you know, except for the one working fusion reactor we have nearby. Bit awkward that it's unshielded, but it does provide power for roughly 1 quintillion people. But in the short term we only have to build the power receivers for our existing fusion reactor, if we want to act like we actually care about global warming.
Re: (Score:2)
The thing is that we will at the very least learn a lot about plasma physics and materials and will get some useful other tech and devices out of it.
Oh, likely so. Far more practical than the LHC, and even that had some practical offshoots.
Well, given that the WWW is a CERN "offshoot"....
Re: Check the trash (Score:2)
Yup, and 50 years ago we decided not to fund it at a level where it will ever be practical, and guess what? It never became practical! Surprise surprise!
Re: (Score:1)
Says the guy looking for a pay raise in the longest science con in history.
Re: (Score:2)
Is he a string theorist or something?
Re: (Score:2)
Japan's JT-60 was calculated to potentially be capable of Q=1.25, but it never actually achieved it.
By current calculations, a tokamak of sufficient size can achieve net positive- but we have not done it.
This lattice-confinement fusion is also nowhere near Q=1, so I'm not really sure why this is news, other than it's yet another novel way to cause inefficient fusion reactions.
Re: (Score:2)
"This lattice-confinement fusion is also nowhere near Q=1"
Yes, it is. Only converting its output into electricity is below Q=1, facepalm.
Re: (Score:2)
They were able to measure approximately 4.25MeV to 4.54MeV with 2.9MeV of input.
The 4.25 to 4.54 is including the 2.9, giving a total system Q value of 0.46 to 0.56.
The only thing novel about this, is that is a lot better than expected.
Re: (Score:2)
It's a dupe (Score:4, Interesting)
not only is it a dupe. It's cold fusion with "cold-fusion" crossed out and "fish license" written in
Re: (Score:3)
Look for unwanted electron accelerators
I had a 32" one [wikipedia.org] until it died and I replaced with a 40" LCD version.
Re: (Score:2)
I got rid of my CRT TV and monitor years ago.
dilithium crystals (Score:1)
Yes (Score:3)
We'll call it the Betteridge Drive.
Unlikely because Betteridge's Law Probably Holds (Score:3)
What is clever is that they have all the ingredients they need in a single package: the heavy metal nucleus to cause the electrons to bremsstrahlung and emit a gamma ray plus a dense concentration of deuterium right next to it.
However, the less good part is that the process is bound to be incredibly lossy. Not all
Re: (Score:2)
I strongly suspect that the net effect will not result in a net release of energy because of all the energy spend on wasted electrons that do not cause fusion.
Wasted = turned into heat. Say only 1% of input energy causes fusion, but that fusion releases WAY more energy than the 1% put in. And say all energy released (both remaining 99% and fusion-produced) is released as heat. Then you'd still have net energy out: X energy in, >X energy out.
In other words: as long as fusion takes place, even a very inefficient process could still be useful. Of course the "if fusion takes place" is a big if.
Re: (Score:2)
Re: (Score:2)
Only problem is if you try to activate it after a positive headline it suffers a logic implosion that releases an infinite improbability blastwave.
No (Score:3)
But just maybe, by the power of Slashdot dupes [slashdot.org].
Re: (Score:2)
Yeah this is a massive dupe.
Non Paywalled (Score:2)
Let's get it working first... (Score:2)
After we've done that, we can worry about where we choose to deploy it.
Re: (Score:2)
It's not strictly implied - but unless a process relies on the absence of a strong gravitational influence (exactly like this one doesn't), it will work just as well on Earth as well.
As a general rule a strong gravitational field makes everything easier, with the exception of large scale or high-precision construction, and a few kinds of manufacturing. Though hopefully that list will get longer once it becomes affordable to do things in orbit so people can start exploring the potential.
Re: (Score:2)
Because fusion has been demonstrated both on Earth (NIF, ITER, Ivy Mike, etc.), and in space (stars)?
Re: (Score:2)
Ivy Mike
LOL.
I mean, you're not wrong... but subjecting heavy hydrogen to conditions more severe than the our local stellar fusion reaction can even produce is probably not the best example of "fusion" in any useful sense of the word.
Two of the same? (Score:2)
Re: (Score:2)
No it's not. Every way current theory knows how to initiate fusion is a kinetic process, but in general the more you can avoid thermalizing* that kinetic energy the better. And if there's anywhere that's ripe for undiscovered physics, quantum mechanicsis it.
*thermal energy displays a characteristic (Gaussian?) distribution of kinetic energy - most of which is useless for triggering fusion reactions. Systems like the Polywell explicitly strive to avoid, or at least delay, thermalizing the plasma to maximize
Re: (Score:2)
Perhaps an example is in order:
Head-on collisions from sufficiently high-energy proton accelerators will reliably initiate fusion, but since the kinetic energies of the particles in an accelerator are all tightly confined to a very narrow band of speeds, that kinetic energy is not generally considered thermal energy.
Misalign those beams so that they form a chaotic plasma instead, whose particles have the same average speed, but a much wider _range_ of speeds, and you've got a thermal plasma - and need a m
Re: (Score:2)
Re: (Score:2)
Well for starters, it can easily make a difference of several hundred thousand degrees or more, and thus the difference between net energy production, and pissing energy down the oubliette in a fool's quest.
More explicitly, it's the difference between whether a reaction is governed by kinetics, where energy can theoretically be converted from one form to another with 100% efficiency, or thermodynamics, where the best you can hope for is to recover energy based on Carnot-cycle efficiency.
In this particular c
Re: (Score:2)
... versus having to heat the entire system to millions of degrees to get the same fusion rate...
due to chaotic collision of particles traveling at wildly different speeds and directions.
Re: (Score:2)
Re:Two of the same? (Score:5, Informative)
It can vary wildly based on the reaction. I'm not exactly a nuclear physicist myself, but as I recall there's a few different possible outcomes depending on the exact nature of the reaction. And some reactions actually have several different possible outcomes with each having a different probability of occurring.
Gamma rays are a common result, and for many reactions you'll just get a single high-energy gamma-ray photon.
High-speed electrons or positrons are also fairly common, as an unstable nucleus "settles down" by transmuting one of the nucleons, e.g. a proton converts to a neutron or vice-versa, in which case some of the fusion energy gets released as its kinetic energy. Neutrinos can often be ejected as well, tohugh I think (don't quote me) that they usually don't carry much energy.
And finally entire nucleus fragments can be ejected- usually either free neutrons that will fairly rapidly decay into hydrogen. or He4 nuclei, which are extremely stable. P-B11 fusion does that, with the resulting nucleus quickly fragmenting into three He4 nuclei all moving at almost exactly the same speed.
The simplest way to convert all of those (except neutrinos) to useful energy is to let them hit the reactor shielding to produce heat, and from there steam, but there are other options. At any rate the fusion has already happened at that point, so it's not really relevant to a claim that fusion is thermal, which would be a (mostly) inaccturate characterization of the conditions necessary to _cause_ fusion, which basically comes down to slamming nuclei into each other at high enough speeds. Since temperature = average speed at the atomic scale, high enough temperatures will do the job, but thermalized energy means that particles are moving at a really wide range of speeds - some far faster than the average, some almost motionless, so the odds of a random collision having enough energy to trigger fusion is far lower than if thermalization can be avoided so that all the particles are moving at nearly the same speed so that *every* collision can potentially trigger fusion.(potentially - I believe there may also be some geometric alignment issues that may factor in to the reaction probability. )
Re: (Score:2)
Re: (Score:2)
You're welcome.
Re: (Score:1)
Okay, how about "warm fusion" then
Re: (Score:3)
The material setup, but NOT the conditions. X-ray acceleration is supplying the kinetic energy necessary to overcome the Coloumb barrier and initiate traditional high-kinetic-energy hot fusion.
The similarities do however suggest that "cold" fusion could be explained in terms of highly localized hot fusion thanks to random variations in the kinetic energy of confined nuclei - some techniques such as high-frequency agitation even explicitly attempt to cause that. But in general, accepted theory does not ju
Re: (Score:3)
In fact, one speculation about cold fusion was the possibility that deuterium trapped in the crystal lattice of palladium was in fact involved in very small scale hot fusion. That didn't pan out, but it does raise the related question "OK, so can we make that happen somehow?".
Surely (Score:3)
Ask slashdot (Score:2)
Yes ask this on slashdot, the best place to reach future and past Nobel prize winners.
Now we are 5 years away ... (Score:2)
Re: (Score:3)
We are not 5 years away from another dupe on Slashdot!
Re: (Score:3)
Fun fact - progress towards net-positive fusion is actually still in line with those original 20-year forecasts made all those decades ago - provided you measure it in terms of progress-per-dollar rather than progress-per-year. Unfortunately funding has been falling steadily, and we're still a long way from reaching the funding goals that those perpetual 20-year forecasts assumed would be reached within 20 years.
It's like someone promising they can build you a nice apartment complex in 20 months if you pay
Project Orion? (Score:1)
I thought the future was lots of bombs slung out of the back of the spaceship and exploded:
https://en.wikipedia.org/wiki/... [wikipedia.org]
oh please, how will this ever work (Score:1)
without dilithium crystals ?
Sounds perfect for unmanned craft. (Score:2)
This'll do the job of a Plutonium battery.
Relatively low power but functional over very long time scales.