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The temperatures and pressures are too high to hold for long enough periods to get as much energy from the reaction (or more) as was put in to start it.
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∙ 12y ago
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Why can't we control fusion?
So far it has proved too difficult to get it started, so control has not been a problem
Why do you use fission reactors not fusion reactors?
No way has yet been found to reach break-even in a controlled fusion reaction and get as much energy out as was needed to put in to start the reaction. To make a reactor you need to go past break-even and release extra energy.
Is nuclear fusion used as an energy source in power plants?
Nuclear power plants use controlled atomic fission to generate electricity. Atoms of the fissile material are split and part of their mass is converted to energy in addition to neutrons being ejected from the nucleus. These neutrons impact other atoms within the fissile material which then release further energy and more neutrons. The reaction is controlled by absorbing most freed neutrons with material so an uncontrolled chain reaction doesn't occur like the atom bomb used in WWII. The energy released produces heat (and radiation) which heats liquid into steam turning turbines connected to electric generators to make electricity. The highly radioactive spent fuel is a dangerous waste product that must be warehoused for many lifetimes. Conversely, the simplest type of nuclear fusion, which may become a reality this century, converts hydrogen atoms into helium atoms and produces no radioactive waste products.
How does the energy released by fusion compare in magnitude with that released by fission?
In a fission reactor which has been operating at a steady power level, on shutdown the fission reactions stop at once, but the radioactivity of the fission products in the fuel still produces thermal energy. This is about 6.5 percent of the previous power level immediately, dropping to about 1 percent after 1 hour. In the case of fusion, there are no fission products so this comparison does not exist, in fact if fusion reactors can ever be made, this is one of the advantages over fission reactors.
What is the difference between a fission reactor and a fusion reactor?
In simplest terms, nuclear fission involves splitting atoms apart to make energy. Fusion involves smashing atoms together to make energy. Fusion reactors are currently entirely theoretical and do not exist. The main problem with fusion is figuring out how to get more energy out of the process than you put into making the fusion happen. Right now, the sun is the only place where fusion takes place on any meaningful scale.Another Answer:From a power production point of view, i.e. a controlledreaction, it is true that we have not been successful with fusion power. However, from a weapons point of view, i.e. an uncontrolled reaction, we have been successful. This is the basis of the hydrogen bomb. Interestingly, the hydrogen bomb requires so much energy to set it off that we use a fission bomb (the original atomic bomb) to initiate the fusion reaction.
Is it possible to contain plasma so it can be used as a weapon?
Not presently. We do not have a container for plasma. If we did, we would also have fusion reactors, which we do not.
What are ideal places for fission and fusion?
Fission takes place in nuclear reactors, which are useful to produce electricity. Fusion has not yet been harnessed on earth, so the only place it happens is in stars
Are there any fusion reactors operating now?
i believe they are still in the testing phases... but I have heard of one that was in operation not sure I would have to do some research again? So going on from here, Fusion reactors are still being tested small scale, and according to wikipedia, the worst source in the world. They are not expected to be used commercially untill atleast 2050.
Why are fusion reactors not yet present day reality like fission reactors?
Only beacuse of starting trouble. Any way we need billion kelvin temperature to start with for which we have to rely on fission reaction. One more important point we cannot have a controlled fusion reaction as we do so in fission ie nuclear reactor using control rods.
Does trap hole work on fusions?
A Fusion Summon, or the Summoning of any Monster (Synchro or Fusion) from the Fusion Deck (Extra Deck) is a special summon and so Trap Hole will not work on it.
What is the major disadvantage of using nuclear fusion reactors?
We don't have nuclear fusion reactors. We have not been able to sustain a controlled fusion reaction for more than a brief moment in time, and of more than a small amount of power. Only the Sun and stars have controlled fusion reactions, and Hydrogen bombs have uncontrolled fusion reactions. The problem is in maintaining the extremely high temperature and pressure required to sustain a fusion reaction, while at the same time containing the plasma that results from it. It is so hot that no container will hold it. We can build magnetic "bottles" so to speak, but the enormous flux required to do that requires super magnets, and that requires super-conductors and super-cold temperatures. Placing a super-hot plasma flow within the boundaries of a super-cold magnet is just not something we have accomplished yet. We are working on it, but, barring any stupendous discovery, I think controlled fusion reactors are at least 50 or a 100 years away.
Why can't we control fusion?
So far it has proved too difficult to get it started, so control has not been a problem
How many years of nuclear power are left?
With fission reactors, probably at least a hundred years. By then fusion may be usable and this will last indefinitely, as so much deuterium is in the oceans.
Why can't net fusion power be produced by linear particle acceleration?
Linear accelerators used in particle physics research are typically geared to accelerate a small amount of matter to extremely high energies. The energy required to do this is huge, but the energy gain not so. The trick in a fusion plant is not to achieve fusion, but to achieve a self-sustaining fusion reaction, like in the cores of stars, so that the output exceed the input.Particle accelerators may be used in fusion reactors to heat the plasma to temperatures required for fusion by neutral beam injection.
Why do you use fission reactors not fusion reactors?
No way has yet been found to reach break-even in a controlled fusion reaction and get as much energy out as was needed to put in to start the reaction. To make a reactor you need to go past break-even and release extra energy.
Does fusion occur on Earth?
No, there are no recorded situations in which sustainednuclear fusion has been accomplished here on earth. In nuclear weapons, fusion is accomplished only for a split second. And the fusion experiments we're developing are yet incomplete.
What is the major disadvantage of using nuclear fusion?
We don't have nuclear fusion reactors. We have not been able to sustain a controlled fusion reaction for more than a brief moment in time, and of more than a small amount of power. Only the Sun and stars have controlled fusion reactions, and Hydrogen bombs have uncontrolled fusion reactions. The problem is in maintaining the extremely high temperature and pressure required to sustain a fusion reaction, while at the same time containing the plasma that results from it. It is so hot that no container will hold it. We can build magnetic "bottles" so to speak, but the enormous flux required to do that requires super magnets, and that requires super-conductors and super-cold temperatures. Placing a super-hot plasma flow within the boundaries of a super-cold magnet is just not something we have accomplished yet. We are working on it, but, barring any stupendous discovery, I think controlled fusion reactors are at least 50 or a 100 years away.
