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Two-Laser Boron Fusion Lights the Way To Radiation-Free Energy
ananyo writes "Fusion unleashes vast amounts of energy that might one day be used to power giant electrical grids. But the laboratory systems that seem most promising produce radiation in the form of fast-moving neutrons, and these present a health hazard that requires heavy shielding and even degrades the walls of the fusion reactor. Physicists have now produced fusion at an accelerated rate in the laboratory without generating harmful neutrons (abstract). A team led by Christine Labaune, research director of the CNRS Laboratory for the Use of Intense Lasers at the Ecole Polytechnique in Palaiseau, France, used a two-laser system to fuse protons and boron-11 nuclei. One laser created a short-lived plasma, or highly ionized gas of boron nuclei, by heating boron atoms; the other laser generated a beam of protons that smashed into the boron nuclei, releasing slow-moving helium particles but no neutrons. Previous laser experiments that generated boron fusion aimed the laser at a boron target to initiate the reaction. In the new experiment, the laser-generated proton beam produces a tenfold increase of boron fusion because protons and boron nuclei are instead collided together directly."
Hooray! Fusion power is now only 20 years in the future! The absence of fast neutrons really is a breakthrough, though: the less radioactive a reactor itself becomes over time, the easier the cleanup at the end of its life.
Socialism: a lie told by totalitarians and believed by fools.
Well, nuclear reactions that we can turn off like laser-initiated fusion are a lot nicer than the alternatives. The inside of your car engine is a raging inferno shot with electric sparks and compressed with inexorable steel cylinders. That doesn't keep you from going on a nice drive with your sweetie.
Bruce Perens.
Robert Bussard's fusion project at Energy Matter Conversion Corporation was aimed at investigating Proton-Boron fusion, because it is clean and produces no high-energy neutrons. I was really hoping this was a follow-on to that work. The device Bussard called a Polywell actually shows some serious potential to revolutionize nuclear power globally. It even shows enough promise that the US Navy has been funding some small-scale experiments. It's unfortunate that Bussard died before he could see the potential of the Polywell realized, but it would be nice to see it succeed none the less.
Reinvent the wheel only at either a lower cost, greater effectiveness, or your own personal enrichment and satisfaction.
Although similar in concept, that particular nuclear mechanism is always refered to as alpha particle decay. Fission is typically used when
a) a heavy nucleus
b) splits into two similar sized pieces, plus some detritus.
I'll take fusion any day over "renewables" - fusion should be able to pack a few GWe into a few hundred or thousand acres of space. Renewables, because of their inherent low energy density, will force us either to conserve or use most of our available open land for energy production. The promise of fusion is really low cost energy without limits. Given that everything we do and everything we aspire to requires more and more energy, I'd much prefer a pure fusion-driven future where conserving energy was a quaint notion.
Also, which fossil fuels exactly have we stolen from third world countries? Most of our power generation in the US comes from coal, which we produce almost exclusively domestically. Most of our natural gas comes from Canada, which isn't exactly a third world country. The only thing we import in scads in oil, and I guarantee, those who control the oil aren't getting stolen from. They're being paid very well. The wealth may not be very evenly distributed in the destination country, but that's hardly because the West "stole it".
No. Boron first absorbs a proton (fusion) and becomes an unstable isotope of carbon, which then splits (fission) and gives off X-rays, gamma radiation, and alpha particles, and a few neutrons.
You need a translation not a citation..
'After huge effort to drown nuclear energy in red tape, escalating build costs to many times their real cost - while at the same time
stopping any form on innovation in cleaner/safer/more efficient forms, we have finally achieved the point where its price/performance
does not wipe the floor with everything else'
And for bonus points throw in a little 'while of course ignoring the actual ecological and human damage of competing generation methods
as those are OBVIOUSLY clean, since they dont use evil nasty RADIATION (and where they do, we will ignore it)'
Make a little more sense now?
For anyone that wonders: french research agency CNRS has thousands of small research teams, which are each commonly led by a research director. A CNRS research director is like a university professor, except he/she is not in charge of any teaching.
It's not a problem, it's an advantage.
You get a 3X +2 Helium nucleus (aka alpha) at 8.7 GeV. Since the particles are charged, you can convert their energy to a usable electrical current directly. (Think field windings of a generator, except there is no winding, just a moving charge.) Neutrons have the disadvantage of _requiring_ a thermalization process to capture their energy.
The disadvantage of the alpha is that it is _easily_ thermalized. You need to keep everything out of it's way until you can extract its energy. This implies super deep vacuum, or a super tiny machine so that the energy conversion device is within the slowing down length of the alpha. The slowing down length of an alpha in air is on the order of a centimeter, IIRC.
Of course, I'm assuming that direct conversion is superior to thermal conversion. If thermal conversion is superior, then just thermalize the alpha just like a neutron, in a big tub of water. Just make sure your tub is grounded to prevent charge buildup.
That doesn't keep you from going on a nice drive with your sweetie
To be fair, it's fairly difficult to drive one handed.