Arob Posted February 9, 2008 Posted February 9, 2008 Okay So as I understand it,the number three reason to settle the moon (industry and tourism are #1 and #2) is the recovery of Helium 3 by settlers with funky combines out there on the sea of tranquility harvesting the lunar soil for the precious helium isotope - this is a product of the Sun's fusion reaction that is not found on earth as it too easily blends into our atmosphere - but on the moon it becomes trapped in the lunar regolith of the moon dust which is a meter thick in places. This rare and valuable element isotope is the proposed main ingredient in fusion energy, yet there is very little on Earth. Question - how far along are scientists with fusion reaction? Which scientists exactly? and the demand for Helium 3 and who is producing H3 now, and how are they doing it? I was told that one space shuttle load of H3 could power the continental US for five years... is this true? Also, what bi- product elements are created in a Fusion reaction? Does this work like a conventional power plant - heat water - make steam - turbines etc or could fusion power be harnessed in a revolutionary new way?
YT2095 Posted February 9, 2008 Posted February 9, 2008 this isn`t really a Chemistry question, so if the Physics lads don`t mind... *Thread Moved*
Klaynos Posted February 9, 2008 Posted February 9, 2008 Ok, I think as for how far along we are and who, wikipedia is a good place to start: http://en.wikipedia.org/wiki/JET http://en.wikipedia.org/wiki/ITER JET is an older system, ITER is yet to be built. The greatest fusion reaction in terms of energy produced is H -> He4... Where the bi-products would be He4, I'm only really familiar with Fusion reactors when we talk about stars where there's two main methods, both generate the same energy, but require different starting elements...
D H Posted February 9, 2008 Posted February 9, 2008 The greatest fusion reaction in terms of energy produced is H -> He4That is a bit of an oversimplification. Four protons do eventually produce helium-4, but it is via a sequence of reactions called the proton-proton chain reaction. The fusion reactions that start the chain involve proton-proton interactions which (a) have proven to be very hard to control and (b) don't produce nearly as much the fusion reactions that end the chain. One of these terminal reactions is the fusion of two He3 nuclei, which forms a He4 nuclei and two protons. This final step represents the bulk of the energy released in the proton-proton chain. This is why He3 is so prized for fusion. Unfortunately, He3 is so rare and so expensive that we have not tried building a large-scale fusion reactor that uses it. We don't know if the Moon has the quantities of He3 that some hypothesize, we don't know if we can mine it, and we don't know if we can build a viable He3 fusion reactor. Using He3 as a rationale for lunar missions is a stretch. It involves two many conjectures.
Klaynos Posted February 9, 2008 Posted February 9, 2008 That is a bit of an oversimplification. Four protons do eventually produce helium-4, but it is via a sequence of reactions called the proton-proton chain reaction. The fusion reactions that start the chain involve proton-proton interactions which (a) have proven to be very hard to control and (b) don't produce nearly as much the fusion reactions that end the chain. One of these terminal reactions is the fusion of two He3 nuclei, which forms a He4 nuclei and two protons. This final step represents the bulk of the energy released in the proton-proton chain. This is why He3 is so prized for fusion. Unfortunately, He3 is so rare and so expensive that we have not tried building a large-scale fusion reactor that uses it. We don't know if the Moon has the quantities of He3 that some hypothesize, we don't know if we can mine it, and we don't know if we can build a viable He3 fusion reactor. Using He3 as a rationale for lunar missions is a stretch. It involves two many conjectures. It is an over simplification but there are 4 or 5 methods which I know of, not all of which are proton-proton chains, but that is the greatest energy change still...
Roger Posted February 16, 2008 Posted February 16, 2008 Question - how far along are scientists with fusion reaction? Which scientists exactly? This guy has already fused HE. Dr Gerald Kulcinski of the U of Wis and Apollo Astronaut Harrison Schmidt are 2 big advocates of He fusion. Kulcinski uses Inertial Electrostatic Confinement to fuse He. Kulcinski and his IEC fusion device. In operation. Meanwhile the late DR Bussard had developed his Polywell Fusion device, and completed Dueterium fusion test runs before his recent death. His work contines under DR Nebel, formerly of Livermore. Polywell may be able to fuse Boron11, using the Proton, Boron collision. Dueterium and Tritium fusion creates neutrons, which degrade the materials in the fusion reactor and can hurt humans. IIRC He and Boron are aneutronic fusion, no, or nearly no neutrons. Therein lies the advantages of these 2 fuels. Dr Bussards WB-6 Polywell in operation in 2005. and the demand for Helium 3 and who is producing H3 now, and how are they doing it? The only source on earth for He3 comes from decommissioned nuclear weapons.
Arob Posted February 23, 2008 Author Posted February 23, 2008 I am really concerned that energy crises will spark another world war with china. I really see a bleak future for mankind with our current dependence on oil... We need fusion power. Will it happen effectively in the next 20 years?
Mr Skeptic Posted February 24, 2008 Posted February 24, 2008 In my lifetime... I think so. In 20 years, probably not.
insane_alien Posted February 24, 2008 Posted February 24, 2008 fission is very viable intermediate towards fusion you know. just bury the waste a kilometer down in some mountain and we'll be sorted.
Mr Skeptic Posted February 24, 2008 Posted February 24, 2008 fission is very viable intermediate towards fusion you know. just bury the waste a kilometer down in some mountain and we'll be sorted. Emptied salt mines are also good for that. (The salt mine is by necessity permanently dry due to its geography, otherwise all the salt would have been leached away.)
Roger Posted February 27, 2008 Posted February 27, 2008 Will it happen effectively in the next 20 years? I think its extremely likely that Polywell fusion will work. If the current research proves out this summer, then its looks we will get 200 million bucks from Uncle Sam, then over 3 to 5 yrs the program will work on proof of concept. Then in 4 to 7 yrs we may see the first standard designs worked up. A lot of "ifs", but never the less in 15 years we would be seeing 1000mw Bussard Fusion Reactor (BFR) production ramped up to commercial levels. At 20 yrs we would see the launching of Polywells off Earth and to the Moon, to power Lunar bases, or stations in orbit. As well as Fusion powered space craft capable of making runs to Mars or Saturn and Jupiter. Fusion will give us the Solar System.
Brian H Posted April 27, 2008 Posted April 27, 2008 All will be trumped by the Focus Fusion p-B11 initiative. Its timeline is about 8 years. The reactor/generator costs are projected at ~$200,000 per, 5 GW capacity, output at $0.002 / kwh.
swansont Posted April 27, 2008 Posted April 27, 2008 Most fusion initiatives have promised results in "about a decade." How is this one any different, other than being led by the author of "The Big Bang Never Happened?" A lot of bells go off in going into the details of this. The web site expends effort differentiating it from cold fusion and ZPE. The billion-degree effort is called "Lerner Theory" — an apparently self-named process. The papers listed are in ArXiv, but the citations for peer-reviewed literature are absent so far as I can see. This prediction of $0.002 / kWh, before a working device has even been built — remember, fission was going to be "too cheap to meter." Sorry, but absent any substantive science and engineering to support this, it registers too high on the BS-meter for me to take it seriously at this time. Feel free to buttress your claims.
Zephir Posted April 27, 2008 Posted April 27, 2008 ...Do Fusion Reactions need Helium 3? Of course not, it's just the easiest fusion reaction, which can be even catalyzed by free neutrons. But for example the Lithium 2H-6Li fusion is much cleaner source of energy producing stream of &-particles with low amount of neutrons, which can be utilized into electricity directly - it "just" needs a 500x higher activation energy (temperature x time factor) for ignition. But here's a neat proposal of inertial Z-pinch plasma fusion involving the lithium deuterides, which I consider a quite feasible.
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