5 ms·

I'm not a specialist but here is what I think I know (I'm talking with the point of view of a Frenchman, who consumes most of his electricity from (fission) nuc

by jylam 2y ago

I'm not a specialist but here is what I think I know (I'm talking with the point of view of a Frenchman, who consumes most of his electricity from (fission) nuclear power plants): 1/ Uranium is not a renewable (quite the opposite), needs to be mined and treated (which is expensive and very polluting), and not present at the required concentrations in most of the world (this creates geopolitical issues). 2/ Fission nuclear plants require a well functioning [state|government], and no war. A (conventional) strike on a nuclear power plant can have devastating and lasting consequences. Even a random terrorist group can do that. 3/ I've read that "Ultimately, researchers hope to adopt the protium–boron-11 reaction, because it does not directly produce neutrons, although side reactions can" (that's a wikipedia quote, but I've read that already from other sources). So fusion doesn't seem the best option on the short term, because of the complexity and cost of research, but definitely seems to be the very best option in the middle and long term. And we made the short term catastrophic choice already with coal and oil, it'll be good to learn from that. Or maybe I'm totally wrong.

adrian_b 2y ago
Deuterium is also not renewable, even if it is more abundant than uranium. The H1-B11 reaction would be a much better energy source than anything else, but for now nobody knows any method to do it. There is no chance to do it by heating, but only by accelerating ions, and it is not known how a high enough reaction rate could be obtained.
- rnhmjoj 2y ago
  I'm curious, what are you considering for stating that deuterium is not renewable? AFAIK there's an essentially limitless supply in the form of HDO in the oceans[1] and there are cost effective methods[2] to isolate it. [1]: https://en.wikipedia.org/wiki/Semiheavy_water https://en.wikipedia.org/wiki/Semiheavy_water [2]: https://en.wikipedia.org/wiki/Girdler_sulfide_process https://en.wikipedia.org/wiki/Girdler_sulfide_process
  - adrian_b 2y ago
    If you are able to say that there is a limitless amount of deuterium in the oceans, than you can say the same about the amount of uranium in the oceans, even if the amount of dissolved uranium is about one thousand times less. Both the amounts of deuterium and of uranium in the solar system are finite and smaller than of the abundant elements. Moreover, the natural processes that create deuterium and uranium within a normal stellar system are slower than those that destroy them, so there is no chance of their quantities ever increasing. Unlike using other chemical elements to make some stuff, using deuterium or uranium for producing energy destroys them without any means to regenerate them, so it is by definition a non-renewable process. The hydrogen (protium) in the Sun is also non-renewable, but its quantity is enormous in comparison with the amount of deuterium existing on Earth (and the amount of energy that the Sun produces per proton is greater than the amount of energy that can be produced per deuteron). Like deuterium is extracted from sea water, uranium can also be extracted from sea water, where it is one of the most abundant metals, except for the alkali metals and the alkaline earth metals. However the energy required for extracting uranium is significantly higher, due to its much lower concentration than deuterium (though deuterium is difficult to separate due to its similarity with the lighter isotope of hydrogen, while for the uranium ions much more efficient chemical reactions would be possible, which would bind uranium ions without being affected by the other dissolved ions).
- perihelions 2y ago
  Then wind power is not renewable either! The saturation wind power potential of this planet (250 terawatts?), integrated from now until this planet ceases to exist, is a finite number—and it is actually a smaller number than this planet's deuterium resource.
- ben_w 2y ago
  > Deuterium is also not renewable, even if it is more abundant than uranium Technology correct, in that after around a hundred trillion years even the red dwarf stars will have stopped burning hydrogen. But last I checked as yet there is no known way to harness the only (and even then merely suspected) infinitely renewable energy source: the expansion of the universe.
  - fragmede 2y ago
    Just tie the end of an infinitely long string to the edge of the universe and have it pull on a generator to spin it.
    - DoctorOetker 2y ago
      I would certainly like to see serious critical analysis and calculations of such hypothetical setups by physicists. Would such a setup slow down the local expansion (action and reaction)? Since iron is essentially a nuclear ground state, a steel cable being lengthened seems like the least worse mass loss imaginable.
  - adrian_b 2y ago
    The amount of deuterium contained in a planet is a very small fraction of its hydrogen content. The amount of hydrogen contained in a medium-sized planet like Earth is extremely small in comparison with the amount of hydrogen contained in a star. The amount of energy that can be produced by fusion per deuteron is smaller than the amount of energy that is produced in stars per proton. With all these factors multiplied, the amount of energy that could be obtained from all the deuterium contained in Earth is many orders of magnitude smaller than the energy produced by the Sun or by any other star. Moreover, the energy obtained from fusion could never exceed a very small fraction of the energy received by Earth from the Sun as light, otherwise it would lead to a catastrophic warming of the Earth. Nuclear fusion reactors are not really useful for solving Earth's energy problems. They could have a crucial importance only for the exploration of the Solar System and for providing energy for human bases established on Moon, Mars or other outer planets. For Earth the only problems worth solving are how to make better batteries, including very large capacity stationary batteries, how to make other large capacity energy storage devices, e.g. thermal devices, and how to improve the energy efficiency of the methods used to synthesize hydrocarbons from carbon dioxide and water. Making hydrocarbons at large scale from carbon dioxide would be the best way to sequester carbon dioxide, offering the choice between just storing the carbon in safe products (paraffin like) and using a part of the synthesized hydrocarbons for generating energy in a carbon-neutral way.
to11mtm 2y ago
1: Well if society could get at least some of their shit together we could do breeders. Alas, someone shot an RPG at Superphenix and that put a damper on a lot of things... But it's not impossible. Japan seems to do most things decent from a 'security' standpoint, also interestingly for all of the other 'grey-market' stuff out there in the category of "shouldn't be radioactive but is" I have yet to find anything about AliExpress selling fissiable materials. 2: Yes and no and how much do you want to spend to improve the breach/damage ratio. i.e. PBRs have relatively low risk under a number of circumstances but have higher operating/etc costs. I should also possibly question, what are the potential failure modes of 'not short timeframe fusion reactions'? I honestly have no clue whether they would quickly cease or if there are other potential side effects. 3: Agreed that neutron stuff can be solved in many ways, I do have some questions about maintaining that across various fusion designs. Big challenge is that we aren't 'there' yet. > So fusion doesn't seem the best option on the short term, because of the complexity and cost of research, but definitely seems to be the very best option in the middle and long term. And we made the short term catastrophic choice already with coal and oil, it'll be good to learn from that. Agreed that Fusion is the ideal long term, hopefully my comments didn't cause thoughts otherwise. I think we need more funding into it, and maybe even research as to how to have other renewables (e.x. solar) help feed into the initial startup/restart process for plants. We have had decades without sufficient funding of research. I will say however, especially in relation to my other point-comments, that other countries (re?)embracing fission in the meantime will likely still lead to discovery of better techniques to deal with 'shared' concerns between fission/fusion such as neutrons/weigner engergy/etc

by jylam 2y ago

adrian_b 2y ago

Deuterium is also not renewable, even if it is more abundant than uranium. The H1-B11 reaction would be a much better energy source than anything else, but for now nobody knows any method to do it. There is no chance to do it by heating, but only by accelerating ions, and it is not known how a high enough reaction rate could be obtained.

rnhmjoj 2y ago
I'm curious, what are you considering for stating that deuterium is not renewable? AFAIK there's an essentially limitless supply in the form of HDO in the oceans[1] and there are cost effective methods[2] to isolate it. [1]: https://en.wikipedia.org/wiki/Semiheavy_water https://en.wikipedia.org/wiki/Semiheavy_water [2]: https://en.wikipedia.org/wiki/Girdler_sulfide_process https://en.wikipedia.org/wiki/Girdler_sulfide_process
- adrian_b 2y ago
  If you are able to say that there is a limitless amount of deuterium in the oceans, than you can say the same about the amount of uranium in the oceans, even if the amount of dissolved uranium is about one thousand times less. Both the amounts of deuterium and of uranium in the solar system are finite and smaller than of the abundant elements. Moreover, the natural processes that create deuterium and uranium within a normal stellar system are slower than those that destroy them, so there is no chance of their quantities ever increasing. Unlike using other chemical elements to make some stuff, using deuterium or uranium for producing energy destroys them without any means to regenerate them, so it is by definition a non-renewable process. The hydrogen (protium) in the Sun is also non-renewable, but its quantity is enormous in comparison with the amount of deuterium existing on Earth (and the amount of energy that the Sun produces per proton is greater than the amount of energy that can be produced per deuteron). Like deuterium is extracted from sea water, uranium can also be extracted from sea water, where it is one of the most abundant metals, except for the alkali metals and the alkaline earth metals. However the energy required for extracting uranium is significantly higher, due to its much lower concentration than deuterium (though deuterium is difficult to separate due to its similarity with the lighter isotope of hydrogen, while for the uranium ions much more efficient chemical reactions would be possible, which would bind uranium ions without being affected by the other dissolved ions).
perihelions 2y ago
Then wind power is not renewable either! The saturation wind power potential of this planet (250 terawatts?), integrated from now until this planet ceases to exist, is a finite number—and it is actually a smaller number than this planet's deuterium resource.
ben_w 2y ago
> Deuterium is also not renewable, even if it is more abundant than uranium Technology correct, in that after around a hundred trillion years even the red dwarf stars will have stopped burning hydrogen. But last I checked as yet there is no known way to harness the only (and even then merely suspected) infinitely renewable energy source: the expansion of the universe.
- fragmede 2y ago
  Just tie the end of an infinitely long string to the edge of the universe and have it pull on a generator to spin it.
  - DoctorOetker 2y ago
    I would certainly like to see serious critical analysis and calculations of such hypothetical setups by physicists. Would such a setup slow down the local expansion (action and reaction)? Since iron is essentially a nuclear ground state, a steel cable being lengthened seems like the least worse mass loss imaginable.
- adrian_b 2y ago
  The amount of deuterium contained in a planet is a very small fraction of its hydrogen content. The amount of hydrogen contained in a medium-sized planet like Earth is extremely small in comparison with the amount of hydrogen contained in a star. The amount of energy that can be produced by fusion per deuteron is smaller than the amount of energy that is produced in stars per proton. With all these factors multiplied, the amount of energy that could be obtained from all the deuterium contained in Earth is many orders of magnitude smaller than the energy produced by the Sun or by any other star. Moreover, the energy obtained from fusion could never exceed a very small fraction of the energy received by Earth from the Sun as light, otherwise it would lead to a catastrophic warming of the Earth. Nuclear fusion reactors are not really useful for solving Earth's energy problems. They could have a crucial importance only for the exploration of the Solar System and for providing energy for human bases established on Moon, Mars or other outer planets. For Earth the only problems worth solving are how to make better batteries, including very large capacity stationary batteries, how to make other large capacity energy storage devices, e.g. thermal devices, and how to improve the energy efficiency of the methods used to synthesize hydrocarbons from carbon dioxide and water. Making hydrocarbons at large scale from carbon dioxide would be the best way to sequester carbon dioxide, offering the choice between just storing the carbon in safe products (paraffin like) and using a part of the synthesized hydrocarbons for generating energy in a carbon-neutral way.

to11mtm 2y ago

1: Well if society could get at least some of their shit together we could do breeders. Alas, someone shot an RPG at Superphenix and that put a damper on a lot of things... But it's not impossible. Japan seems to do most things decent from a 'security' standpoint, also interestingly for all of the other 'grey-market' stuff out there in the category of "shouldn't be radioactive but is" I have yet to find anything about AliExpress selling fissiable materials. 2: Yes and no and how much do you want to spend to improve the breach/damage ratio. i.e. PBRs have relatively low risk under a number of circumstances but have higher operating/etc costs. I should also possibly question, what are the potential failure modes of 'not short timeframe fusion reactions'? I honestly have no clue whether they would quickly cease or if there are other potential side effects. 3: Agreed that neutron stuff can be solved in many ways, I do have some questions about maintaining that across various fusion designs. Big challenge is that we aren't 'there' yet. > So fusion doesn't seem the best option on the short term, because of the complexity and cost of research, but definitely seems to be the very best option in the middle and long term. And we made the short term catastrophic choice already with coal and oil, it'll be good to learn from that. Agreed that Fusion is the ideal long term, hopefully my comments didn't cause thoughts otherwise. I think we need more funding into it, and maybe even research as to how to have other renewables (e.x. solar) help feed into the initial startup/restart process for plants. We have had decades without sufficient funding of research. I will say however, especially in relation to my other point-comments, that other countries (re?)embracing fission in the meantime will likely still lead to discovery of better techniques to deal with 'shared' concerns between fission/fusion such as neutrons/weigner engergy/etc