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Two-laser boron fusion lights the way to radiation-free energy
- ch4ch4 13y agoLies! It's not radiation-free because light and heat was generated (and thus radiated)!
- meepmorp 13y agoAneutronic, not radiation free.
- batbomb 13y agoIt's emitting alpha particles, but the energies are pretty low.
- meepmorp 13y agoI assume you meant emitting. Omitting alpha particles isn't a problem.
- ISL 13y agoYes, but that's very important. Alphas, especially slow ones, are easy to stop and are good at heating things. Free neutrons are hard to stop and can activate nearby material. An a-neutronic process, especially a clever one that works with comparatively low energies, can be important.
- meepmorp 13y agoSure, if there was no radiation at all, it'd be utterly useless.
- DennisP 13y agoAnd since alphas are charged particles, you may even be able to generate electricity without going through a steam cycle. Tri-Alpha and Lawrenceville Plasma Physics are both planning to do it that way, and papers on petawatt laser fusion with boron have mentioned the same. Resulting energy costs could be dramatically cheaper than fossil.
- Natsu 13y agoI was about to ask about this, because I thought someone proved that it was impossible to get enough energy from aneutronic reactions, and the neutrons cause nuclear activation, which in turn makes the reaction a lot less clean than we'd like.
- knappador 13y agoWe really ought to be investing more broadly in fusion technologies. Please spread the word to scientists that they can back this recommendation if they agree. http://lawrencevilleplasmaphysics.com/index.php?option=com_lyftenbloggie&view=entry&year=2013&month=09&day=23&id=105%3Aopen-letter-on-fusion&Itemid=90 http://lawrencevilleplasmaphysics.com/index.php?option=com_l... Supporting broader funding will increase the richness of the science in the field, which gives us more angles to understand what works and what doesn't. I support funding an array of approaches instead of going all-in on ITER that seems to have no future, but I'm not a professor.
- bayesianhorse 13y agoITER seems to be the best bet that can get financed currently...
- InclinedPlane 13y agoITER is a mess. It's a stereotypical government program that will do little to advance fusion science and will take so long to build and be so expensive that it will be of questionable value even if they manage to finish it.
- rpedela 13y agoITER is crazy expensive unlike the project linked above which has spent about $1 million total. Tokamak designs have been around for decades and still have not achieved commercial viability. I think ITER is a long shot at best. Lawrenceville Plasma Physics seems to be much farther along than some of the other well-funded projects. Of course, who knows who will do it first and when. I sure don't. But we should be funding as many possible designs as we can not less.
- jws 13y agoReaders may be left wondering… • How many protons and nuclei did they have to fling to get one to hit? • How much Boron-11 is there accessible on the planet? • How much energy is released, relative to energy required isolate Boron-11, turn it to plasma and generate a proton stream? (Not in this setup, but could this ever be used for energy production?) • Are there other isotopes to which this proton bombardment technique could apply?
- rubidium 13y ago1) They were creating a plasma from a sheet of boron and sending the protons at that. From the publication: "1 in 300–3,000 protons will be able to induce a p11B fusion reaction". 2) There seems to be a fair but not infinite amount: http://www.rsc.org/periodic-table/element/5/boron http://www.rsc.org/periodic-table/element/5/boron. One site listed $500 per 100g. 3) It doesn't seem that such a calculation is readily available. However, now that the physics has been demonstrated, one can start to entertain such questions. Also, we are continually improving the efficiency of our laser sources, so as those improve the energy cost for this setup decreases. 4) Also from the publication: "Although our results are specific to the p11B case, a similar approach could be used to study the reaction of other light isotopes." Bonus: Actual publication link (I'm not sure if the link is paywalled): http://www.nature.com/ncomms/2013/131008/ncomms3506/full/ncomms3506.html http://www.nature.com/ncomms/2013/131008/ncomms3506/full/nco...
- ars 13y ago2) There is a lot of Boron 11, it makes up 80% of Boron. 3) Yes! You can use this for energy. In fact see my other post - I believe this is the future of fusion. The Boron doesn't need to be a plasma, so you don't need to confine it. You just leave it as a solid and hit it with protons. 4) You can also use Lithium (both isotopes) and Nitrogen (the rare 15 one).
- XorNot 13y agoWhat's more notable is that you can directly convert this to energy - the reaction yields charged particles, which will cut flux and induce current.
- ars 13y agoThis is the future of fusion, not D-T fusion. Or use Lithium instead of Boron. Lithium is even better than Boron because you don't need isotope separation (since both work), and you get more power out of it. The Boron or Lithium doesn't need to be a plasma, and you don't need to confine it. This makes it much simpler to handle. You leave it as a solid and just hit it with protons. Not all the protons will do anything. If you can recycle the energy of the failed protons then the low efficiency can be mitigated. Those that hit will leave behind helium (both H3 and H4) you probably need to remove that to prevent interfering with incoming protons. But there is no other ash to worry about. (And the H3 is very useful - you can even use it for energy.)
- tocomment 13y agoI'm confused as to why it would leave behind h3 and h4?
- sbierwagen 13y agoMass is conserved in nuclear fusion. p+Li6 fusion is a single proton (a bare hydrogen nucleus) smacking into an atom made of 3 protons and 3 neutrons. (Lithium-6) The reaction products have to have the same number of protons and neutrons as what goes in.
- ars 13y agoI meant He3 and He4, sorry.
- electronous 13y agoWhat about a three-laser system?
- samatman 13y agoThe resulting heat could be used to reduce boria to elemental boron, which makes a decidedly energy dense fuel: http://www.eagle.ca/~gcowan/boron_blast.html http://www.eagle.ca/~gcowan/boron_blast.html
- InclinedPlane 13y agop-B11 fusion would be the holy grail for energy, since ordinary Hydrogen is very common, Boron-11 is the most common isotope, and Boron itself is fairly common on Earth (annual production is around a million tonnes). Moreover, the reactor design could be remarkably simple and highly efficient. Power could be directly converted from the plasma to electricity without a need to use heat exchangers or steam turbines. Additionally, the low neutron flux would make the reactor remarkably safe, as would the fusion products (primarily ordinary Helium). However, as far away as D-T fusion energy is today p-B11 is even farther. p-B11 fusion requires plasma temperatures 10 times higher than D-T fusion, making it that much more difficult to build devices capable of inducing fusion. Worse yet, at those conditions the bremsstrahlung radiation loses using conventional plasma confinement technologies would be significantly higher than the power produced by the fusion reactions. What that means is that for every watt produced by fusion that might be converted to a fraction of a watt of useful power there would be more than a watt of power radiated away in x-rays and gamma rays, meaning that it would cool faster than it could be heated by fusion energy, rendering it useless as a power source. In short, p-B11 fusion requires the development of novel approaches to plasma confinement and ramping up their capabilities up to and orders of magnitude beyond what we've done with tokomaks et al today. To say that this would be an enormously challenging scientific and technical enterprise would be a gross understatement. Nevertheless, it very much does warrant continued research. No matter the difficulty there's no way to get to a destination without spending the time on the road there.
- DennisP 13y agoAll true but several groups are attempting it. LPP has published a paper in Physics of Plasmas showing they'd reached 1.8 billion degrees C, well over the minimum required for boron fusion. They claim that bremsstrahlung is suppressed at the extreme magnetic fields they generate, and that this effect is well-known to astrophysicists. There are also papers claiming that side ignition of boron fuel is possible with a 60-petawatt picosecond laser, about six times bigger than our largest today. Tri-Alpha is also attempting boron fusion: http://nextbigfuture.com/2013/06/tri-alpha-energy-review.html http://nextbigfuture.com/2013/06/tri-alpha-energy-review.htm...
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- superkuh 13y agoAfter reading the full text article I was surprised to find the protons from the aluminium foil/picosecond pulse interaction actually come from hydrocarbon impurities that were on the back surface of the foils. If they don't guard that hydrocarbon film on the back of the aluminium from the Boron-ionizing nanosecond pulse then they don't get protons. So that is why the second thinner aluminium film is there; to shield the impurity layer on the thick aluminium film.
- X4 13y agoI would like to say that contrary to software engineering, physical engineers tend to use quirks more often than software engineers, but the reality is that in both worlds quirks are heavily used and accepted. Hence MVP and other quick and dirty delivery models are popularized...