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Can anyone explain tl;dr style how this will produce clean energy? I understand the idea, but how fuel is being produced because it sounds they use small quanti
by funkyy 11y ago
Can anyone explain tl;dr style how this will produce clean energy? I understand the idea, but how fuel is being produced because it sounds they use small quantities of helium which is easily accessible?
- brian-armstrong 11y agoThey're using helium to scale up and test that the various systems work. The actual fusion will likely be done on deuterium and tritium, which are hydrogen atoms with 1 and 2 neutrons respectively. Hydrogen is readily available via electrolysis but you have to get the isotopes of it to serve as fuel. Fusion reactions of this sort are quite clean. The actual reactor will be bombarded by neutrons so parts of it will become radioactive but the effect should be much less than a conventional fission reactor. edit: as for how the actual energy production works, you get deuterium and tritium up to very high temperatures and get the atoms to collide. The kinetic energy in these reactions will be so high that electrostatic repulsion will not be able to prevent the collision (normally, like repels like, but this force can only stop so much energy). once the two collide, the strong nuclear force takes over and forms helium and releases one of the neutrons plus a whole bunch of energy
- funkyy 11y agoGreat, so to produce the fuel you can use energy from reactor, so it is self serving, right? I cannot find any simplified information on how dirty this is, what it takes to produce energy and what is the waste. It just says its clean and revolutionary.
- brian-armstrong 11y agoDeuterium is readily available- you can get it from sea water if you've got the right equipment and enough patience. Tritium is more rare, but you can actually use those released neutrons from the reactor to make some, if I understand correctly. Either way, you only nees just a tiny amount of fuel- fusion reactors leverage e=mc^2 pretty well Unlike fission reactions, there are no leftover radioactive byproducts. There's nothing to bury and there are no carbon emissions (like e.g. coal). The reactor itself does become radioactive but this should be a much easier problem to deal with. Fusion is the transformation that powers the sun. Harnessing nuclear fusion is one of the ultimate acts of power over nature that man can do.
- funkyy 11y agoGreat, explanation like that should be associated to majority of their articles. Sounds like a great thing so good luck to them! Thanks for explanation!
- brian-armstrong 11y agoThis is likely because they have a science bias, not a product bias. This particular team and design will never produce more energy than it will consume. It's specifically made to validate some ideas about reactor design. Fusion reactors become more energy efficient as you scale them up, but also more expensive. As a result, all such designs have to be vetted through a series of cheaper but "nonfunctional" designs. It would be hard for them to extoll all the virtues of this without knowing if this design can work. One possible outcome from this test is that the reactor design, the stellerator, is not presently feasible for power plant design. That would be disappointing but at least they would have paid relatively less to figure that out.
- lmm 11y agoYes - with enough electricity electrolysis is easy, it would likely run on seawater. There are no "fission fragments", nothing heavily radioactive. There is significant neutron radiation while the reactor is running, which over time will mean the reactor components themselves become low-level radioactive - but we're talking the kind of thing that's dangerous for decades, not centuries. The tritium fuel is somewhat radioactive but would float away quickly if released as it's so light. Fusion can only occur under active containment; if the reactor loses power or the containment system fails then all you have is a pile of mildly radioactive plasma (which is not exactly great, but as above, if released into the atmosphere it would fly off into space, there's no risk of it finding its way into rainwater or anything like that). There's no "meltdown" scenario even theoretically; the physics just doesn't create that kind of possibility.
- Tloewald 11y agoOne tiny nit -- the plasma is hydrogen which burns to create water, so there's every chance it will come back as rainwater, it's just not terribly concerning.
- Razengan 11y agoDoes that mean fusion reactors could generate "excess" water which could be used to treat drought-affected areas? Sounds like an eventual win/win!
- lmm 11y agoThere are any number of wonderful things you can do with a supply of cheap electricity :). I believe desalination is largely uneconomic at current electricity prices but used a little in Israel?
- Tloewald 11y agoThe amount of hydrogen produced is minuscule. The energy released is given by E=mc^2 where m is the difference in mass between the Deuterium and Tritium atoms and the resulting Helium atom and neutron. Even a hydrogen bomb doesn't create a significant amount of water (consider that it weighs a few tons, and only a tiny proportion of its mass is converted).
- TheSpiceIsLife 11y agoHow do we harness that 'whole bunch of energy' from a fission reactor? Is the plan to run a heat exchange to produce supercritical steam?
- TheSpiceIsLife 11y agoSorry, I meant to type 'from a fusion reactor', since that's what we're talking about here.