FAQ - Why is fusion so difficult?

If you wonder how/why fusion works, or how/why the Fusor works, look here first.
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Richard Hull
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FAQ - Why is fusion so difficult?

Post by Richard Hull » Tue Jan 17, 2017 5:44 pm

This is a FAQ for those totally ignorant related to nuclear energy, be it fission energy or fusion energy. It will not be extensive or intensive, but lay down a number of issues that should help clear up the question often asked in the title of this FAQ.

****************************FISSION**************************************

Fission has been supplying publicly distributable electricity since 1957. 60 long years of practical, deliverable power to individual Americans.

Fission involves the spliting, (fissioning), of individual atomic nuclei. Energy is released every time a nucleus fissions. This energy is released "binding energy" that held the nucleus together. This binding energy was previously a small part of the mass of the original nucleus. Mass has been turned into energy. This binding energy was placed in the nucleus long ago in some supernova stellar explosion as unfathomable amounts of energy forced lighter unfissionable atoms to merge or fuse. All fissionable atoms are unstable and are just itching to fission. They are naturally unstable due to a storage of that original binding energy forcing nuclei within them to start experiencing an ever urgent and overacrching repulsion from each other due to their positive electrostatic charges. This electrical charge is trying to overcome the nuclear strong force, (binding energy), that forced them together eons ago. In short, they are a loaded gun waiting to go off. If left alone, these ultra heavy nuclei slowly emit helium nuclei as alpha radiation in an attempt to become ever more stable.

Specific Uranium atoms lend themselves to a far more rapid and intense release of binding energy, provided, a simple and rather easy "trigger pulling" event occurs. This event is the simple addition of a single slow neutron to their collective nuclei. This event, effectively, become the straw that breaks the camel's back! Instead of releasing a 5 or 6 million volt helium nucleus, the uranium atom splits releasing many hundreds of millions of electron volts of energy and also throws off two or more neutrons that can further split other neighboring uranium atoms and this process can continue unabated causing an explosion we have come to know as the atomic bomb. The nucelar reaction goes on only so long as there are proper conditions to fission the uranium present.

This same thing happens at the chemical level, (electronic, not nuclear), when we strike a match to a large pile of wood creating a huge bonfire. Our little match applied just the right amount of energy to the pile of wood to release stored electronic chemical energy to create a vast runaway reaction that ceases only after all combustable matter is brought to a more stable chemical state.

The beauty with fission is that we can take an amount of uranium that would make an atomic bomb and assemble it in a fashion that the release of energy can be slowed down to the point where continuous energy can pour out in a usable and controllable amount to make electricity. Just as we can take a pile of coal that could burn down a large town and feed it into a boiler slowly and make a large amount of controlled chemical energy release to boil water and turn a turbine to make electricity. This nuclear assemblage is called a fission reactor. It is abysmally simple, in principle, to make a fission reactor. We are burning Uranium, just as we burn coal in a boiler. Once the nuclear fire is lit it can be controlled and will not go out until all the nuclear fuel is burned. It is a controlled runaway reaction, much like burning coal. It wants to burn!

*****************************FUSION*************************************

Fusion has never produced one watt of usable, distributable electrical energy since its discovery around 1932.

Fusion, on our planet, is the exact opposite in manner of production and occurence from fission. However, it still relies on changing mass into energy, just like fission. In fusion, we do exactly what the supernova and stars are doing throughout the universe. We are taking low mass nuclei and forcing them together to make a lighter mass nucleus. The mass lost related to the two fused atoms creating a lighter fused entity is thrown of as fusion energy. Regardless of mass, all nuclei are forced to resist this union or "fusing" process with all their electrostatic and nuclei powers! Thus, to fuse two nuclei, we are forced to contain them in space and apply huge amounts of energy to force their joining or "fusion". This is the exact opposite of fission where a small match started a continuous process ready to happen. Fusion is a process that needs a monstrous, continued application of energy to force nuclei together that do not want to come together. It is their very nature to never, ever fuse. So great is their refusal to fuse, that should a lot of energy be applied to force their fusion, the release of the resultant energy of fusion forces any other fusible nuclei, (fusion fuel), to blow away from this energy source.

Stars fuse only due to the crushing force of gravity of quintillions of tons of hydrogen gas generating enough heat in their cores to force nuclear fusion, mechanically. A process called "quantum tunneling" occurs due to the press of gravity and heat causing the tunneling effect and fusion. Due to gravity within stars, the fusion fuel really cannot just blow away from the reaction and, thus, the fusion becomes "self-sustaining" in the cores of stars. No star can ever fuse atoms much beyond the mass of carbon. Even the vast energy of a giant star reaches a stopping point in its fusion process. (burns up all of its naturally fusible fuel). In short, the star just loses the power, gravitationally, to fuse any more! Quite often, before this point is reached, a star goes nova. During this extremely short, momentary, hyper-energetic event, atoms more massive beyond carbon can fuse.

In some special over weight stars. A vastly more energetic stellar explosion called a supernova can occur. Only during this type of ultra energetic event can atoms as massive as lead, bismuth and uranium be formed via fusion of lighter elements. Elements beyond iron do not fuse in any normal stellar environment. Only super novae can supply energies needed to fuse nuclei beyond iron.

On earth, we can't even begin to assemble energies or containment to a level that will allow us to fuse to any usable degree, and for any truly measurable period, all but the lightest of elemental isotopes of hydrogen. Even here, we have experienced miserable failure time and time again in an effort to create even a weak sustained fusion process. We have been able to create a momentary fusion reaction in the hydrogen bomb. Sadly, we cannot control this fusion process to create usable electrical energy in the manner we can control the atomic bomb's fission process to create 60 years of distributable electrical energy. Why?

There is no stored, nascent energy in hydrogen that is easily released by a single low energy event that occurs only once to get trillions of its fellow fusion fuel brethren to fuse. Hydrogen atoms are not itching to fuse. Quite the opposite, they, by their very nature, want to refuse to fuse and are naturally repellent to each other. This repulsion is part of the attraction to fusion energy here on earth. The reaction is naturally self-quenching if the reaction suffers a loss of containment or fuel supply, poisoning of its environment or loss of energy needed to keep it going. Fusion can't runaway in an earthly environment, period. It can runaway on earth in the form of a hydrogen bomb due solely to the neutron which can start a fission reaction which can attain a thermal environment among fusion-ready hydrogen isotopes where they fuse for microseconds until the containment fractures and the temperature needed to fuse drops below the level where fusion can continue.

I do find in interesting that the only fusible atoms of low mass that we can even dream of fusing are isotopes of hydrogen, lithium, boron, etc., and every single one contains one of more neutrons. The neutron is one of the most important constituents of any atom that we might choose to fuse or fission. The sun never really fuses raw protium for the bulk of its energy. It makes neutron rich deuterium to really kick off the process in my opinion. P+P fusion is so rare. In an electron rich solar core plasmic environment neutrons must be abundant. Neutrons are the stepping stones to both fusion and fission. We like to think of hydrogen fusion but it really hydrogen isotopes that fuse here on earth. The old animated cartoon of two little H, protiums coming together making helium is a deception.

The above explains why fission is easy and fusion is difficult, on earth. I will not speak to the future here, but only to the past and present and the science involved in the two processes. Remember, fusion is a highly resistive, creational process. Fusion fuel abounds on earth. Fission is a highly prepared, ready-to-go, burning or destructional process. Fission fuel is a rarity and must be mined, processed and separated from, or enriched among one or more of its worthless isotopes.

Richard Hull
Progress may have been a good thing once, but it just went on too long. - Yogi Berra
Fusion is the energy of the future....and it always will be
Retired now...Doing only what I want and not what I should...every day is a saturday.

David Kunkle
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Re: FAQ - Why is fusion so difficult?

Post by David Kunkle » Tue Jan 17, 2017 7:36 pm

"We have been able to create a momentary fusion reaction in the hydrogen bomb."

Even this requires a fission bomb/explosion as an inherent part of triggering the hydrogen bomb. The fission bomb itself is large enough to destroy a small city.
If your experiment needs statistics, you ought to have done a better experiment.

Ernest Rutherford

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Richard Hull
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Re: FAQ - Why is fusion so difficult?

Post by Richard Hull » Tue Jan 17, 2017 8:23 pm

True, only the heat and energy of a fission explosion can start the burn of the fusion fuel in the H bomb. Just another example of how tough it is to start up a limited, yet major, energetic fusion reaction on earth. In a fusion reactor we are limited to just electrical energy sources to start the reaction, and maintain the magnetic containment. Neither of which has ever worked in any attmepted fusion reactor to maintain a controlled fusion reaction over the last 70 years! Billions and billions spent without a micro-watt of distributable electrical energy produced.

Richard Hull
Progress may have been a good thing once, but it just went on too long. - Yogi Berra
Fusion is the energy of the future....and it always will be
Retired now...Doing only what I want and not what I should...every day is a saturday.

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Dennis P Brown
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Re: FAQ - Why is fusion so difficult?

Post by Dennis P Brown » Thu Jan 19, 2017 11:05 pm

Yet in all fairness, a few tokamac experimental devices have achieved essentially break-even for energy in and fusion energy out. That is a vast improvement over the 50's - late 70's and proves that fusion energy is very achievable for this range if one does not mind that such a very low energy device will cost a 1/5 of what a real fission power plant does and that plant will produce well over a 1000 mega-watts continuous.

While the tokamac is likely a dead end, not so the stellarator. Time will tell on that device (relative to ever achieving break-even, not real power for the current test reactor.) But great progress (at not so great a cost considering the cost of a single aircraft carrier, lets say) has been made and the potential payoff is well worth the effort.

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Re: FAQ - Why is fusion so difficult?

Post by Richard Hull » Fri Jan 20, 2017 4:40 am

Regardless of device, I still say that no newborn child today will ever live so long that they will ever see one watt of earth bound, nuclear fusion produced electrical energy come out of their home wall outlet.

Richard Hull
Progress may have been a good thing once, but it just went on too long. - Yogi Berra
Fusion is the energy of the future....and it always will be
Retired now...Doing only what I want and not what I should...every day is a saturday.

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