Ideas for hydrogen fusion

Thread Starter

Motanache

Joined Mar 2, 2015
540
Nearby elements of hydrogen are used in two large research centers:
ITER and Tokamak.

But I'm curious if you have other ideas...........................
 

xox

Joined Sep 8, 2017
579
I honestly don't think fusion will ever be a viable energy source (unless we're talking about solar power). Reason: the energy required to create the appropriate conditions will always exceed the amount generated. I even suspect that many researchers already know this but since there is so much money (grants and other funding) on the line, no one dares to bring that fact to light. Same thing you see with quantum computing; likely impossible, but just too profitable to justify pulling the plug on research.
 

wayneh

Joined Sep 9, 2010
17,153
I honestly don't think fusion will ever be a viable energy source (unless we're talking about solar power). Reason: the energy required to create the appropriate conditions will always exceed the amount generated. I even suspect that many researchers already know this but since there is so much money (grants and other funding) on the line, no one dares to bring that fact to light. Same thing you see with quantum computing; likely impossible, but just too profitable to justify pulling the plug on research.
I'm less skeptical. Folks like LPP Fusion are making interesting progress and aren't really living fat on optimistic investment. The ITER project may be welfare for PhDs but there's only scraps for these smaller projects.

Quantum computing may be closer than you think.
https://www.newscientist.com/articl...uter-test-shows-breakthrough-is-within-reach/
 

nsaspook

Joined Aug 27, 2009
8,667
I'm less skeptical. Folks like LPP Fusion are making interesting progress and aren't really living fat on optimistic investment. The ITER project may be welfare for PhDs but there's only scraps for these smaller projects.

Quantum computing may be closer than you think.
https://www.newscientist.com/articl...uter-test-shows-breakthrough-is-within-reach/
I'm a lot less skeptical of fusion because we know it works until iron with positive energy generation. For heavier elements it needs external energy but that's usually from a massive suns gravitational energy during a nova stage.
 

xox

Joined Sep 8, 2017
579
So you are saying the sun doesn't run on fusion? :confused:
Nope, covered by my disclaimer: "unless we're talking about solar power". ;)

I'm a lot less skeptical of fusion because we know it works until iron with positive energy generation. For heavier elements it needs external energy but that's usually from a massive suns gravitational energy during a nova stage.
The materials used for fusion are in a stable state. This is a problem! Extracting energy from a low entropy system requires energy and that energy must exceed the output. Star formation skirts the issue by exploiting the fact that gravitational force is constant. It is, in a sense, free.

The precursors of fission, in contrast, are already in an unstable state. Just need to raise the energy levels of the atoms high enough to initiate a reaction.

A good analogy is the conundrum of using water as a fuel for engines. Since water is essentially burned hydrogen (and thus a stable, low entropy system) it has to be separated by some means before being used as such which of course requires energy, more energy in fact than the recombination of its parts can produce! Now if you already have the separated components (think rocket fuel tanks) then sure, you can produce lots of energy, but that's just ignoring the fact that at some point in the whole process work had to be performed in order to take it from a low to high entropy state.

Here on Earth there just isn't anything comparable to the massive pressures "freely" available within the interior of stars, so unless we discover some completely new principle that would allow us to achieve that, fusion will probably always remain just out of reach...
 
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nsaspook

Joined Aug 27, 2009
8,667
Nope, covered by my disclaimer: "unless we're talking about solar power". ;)
The materials used for fusion are in a stable state. This is a problem! Extracting energy from a low entropy system requires energy and that energy must exceed the output. Star formation skirts the issue by exploiting the fact that gravitational force is constant. It is, in a sense, free.
The released energy from a fusion reaction like an H bomb comes from the binding energy of the nucleus when the elements were created (Big-Bang, stars, etc...) originally. In 1961, Soviet physicists detonated a 50-megaton bomb. That didn't take the equivalent of a 50-MT bomb of input energy to generate the fusion process and hopefully we will eventually be able to cross the break-even point with controlled steady state or pulsed fusion.

http://www.wolframalpha.com/input/?i=50+megatons+of+TNT+/+c^2 Equivalent mass that underwent fusion from the total mass of the weapon.

http://www.atomicheritage.org/history/tsar-bomba
 
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xox

Joined Sep 8, 2017
579
The released energy from a fusion reaction like an H bomb comes from the binding energy of the nucleus when the elements were created (Big-Bang, stars, etc...) originally. In 1961, Soviet physicists detonated a 50-megaton bomb. That didn't take the equivalent of a 50-MT bomb of input energy to generate the fusion process and hopefully we will eventually be able to cross the break-even point with controlled steady state or pulsed fusion.

http://www.wolframalpha.com/input/?i=50+megatons+of+TNT+/+c^2 Equivalent mass that underwent fusion from the total mass of the weapon.

http://www.atomicheritage.org/history/tsar-bomba
Hydrogen bombs require the assistance of a fission device to get going so not exactly a free lunch. You have to somehow raise the energy levels high enough to overcome the Coulomb force, so what sufficient input sources exist besides gravitation and fission?
 

joeyd999

Joined Jun 6, 2011
4,477
You have to somehow raise the energy levels high enough to overcome the Coulomb force, so what sufficient input sources exist besides gravitation and fission?
The source is irrelevant. The trick is to release more energy via fusion than required to start it. Once energy out > energy in, you've won. The reaction need not even be sustained, as long as you can continuously restart it and repeatedly achieve the above result.

Example: https://en.m.wikipedia.org/wiki/Inertial_confinement_fusion
 

xox

Joined Sep 8, 2017
579
Source matters: lasers and electromagnets require electricity!

And hey, if I'm wrong I'll pay for a round of beers...Atomic Pumpkin alright with everyone?

hero_2017_atomic_pumpkin.png
 

crutschow

Joined Mar 14, 2008
27,727
so unless we discover some completely new principle that would allow us to achieve that, fusion will probably always remain just out of reach...
We don't need a new principle, we just need a sufficiently efficient way to provide the conditions for fusion that will release more energy than it takes to reach those conditions, and it's been determined by many that the theoretical energy required to reach those conditions is much less than the fusion energy released.
So you just need to improve the efficiency of achieving those conditions, not a new principle.
Of course achieving that has proved to be very difficult, but that doesn't make it impossible.

The history of technical advancement is littered with those who said something couldn't be done and than someone did it.
At the start of the last century, many said it was impossible for man to ever fly.
But all that was really needed was a properly designed wing along with a more efficient engine that had a better power to weight ratio.
 

xox

Joined Sep 8, 2017
579
We don't need a new principle, we just need a sufficiently efficient way to provide the conditions for fusion that will release more energy than it takes to reach those conditions, and it's been determined by many that the theoretical energy required to reach those conditions is much less than the fusion energy released.
So you just need to improve the efficiency of achieving those conditions, not a new principle.
Of course achieving that has proved to be very difficult, but that doesn't make it impossible.

At the start of the last century, many said it was impossible for man to ever fly.
But all that was really needed was a properly designed wing along with a more efficient engine that had a better power to weight ratio.
Well that's true, maybe it really is just a matter of refinement. I'm just somewhat of an inveterate skeptic I guess...
 

xox

Joined Sep 8, 2017
579
I'd love you to point out exactly where in my post I discounted that.
Just how much energy do you think these devices draw? We haven't even broken even at this point, thus a seemingly over-optimistic assessment could easily be construed as having discounted that fact.
 

joeyd999

Joined Jun 6, 2011
4,477
...a seemingly over-optimistic assessment could easily be construed as having discounted that fact.
You seem to share -- like a few other members of AAC -- the propensity to read into posts things that aren't there. It's a bad habit. Lose it.
 

nsaspook

Joined Aug 27, 2009
8,667
Just how much energy do you think these devices draw? We haven't even broken even at this point, thus a seemingly over-optimistic assessment could easily be construed as having discounted that fact.
Most Tokamak Fusion plant predictions are of a 'Q' of about 30 at 500GW where engineering breakeven for normal plant operational losses would be a Q of 5.
Record for Q is held by the JET reactor in the UK, at 0.67
https://en.wikipedia.org/wiki/Fusion_energy_gain_factor
 

crutschow

Joined Mar 14, 2008
27,727
I think Tokamak type reactors are way too large, inefficient, and expensive to ever be really practical.
The ITER Tokamak research system being built in France is a very expensive boondoggle, that will likely die at some point, when better techniques for fusion power are developed.

I think the future for fusion is from a pulsed plasma approach, such as being developed by LPP and others, which will be more practical.
It can be smaller (10 megawatts has been mentioned, so it can be located wherever needed) and more efficient, since the fusion products for the proposed boron-proton aneutronic fusion reaction are high energy charged ions which can be directly converted to electricity with magnetic coils around the reactor (no boiler-turbine-generator required).
Aneutronic reactions generate few neutrons, so no significant shielding is required and neutron damage to the reactor is not a problem.
 
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