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Hydrogen is the Universe's most abundant element. Helium is a product of Hydrogen that has undergone fusion. We'll be able to manufacture Helium when Nuclear F

by MAGZine 13y ago

Hydrogen is the Universe's most abundant element. Helium is a product of Hydrogen that has undergone fusion. We'll be able to manufacture Helium when Nuclear Fusion becomes a reality on Earth.

jerf 13y ago
I've pondered that before and realized it could be problematic, so hurray, you've finally prompted me to run the numbers. A fusion reaction that starts from 4 hydrogen atoms (with no neutrons) produces one atom of helium. Let's just ignore the fact that this is a very hard reaction to do, even by fusion standards, and let's just ignore how the energy comes out and deal with raw amounts. Let's produce 1 mole of helium, which according to Wolfram Alpha, is .025 cubic meters of helium at standard temperature and pressure [1]. To produce that mole of helium, we need 4 moles of hydrogen. According to Wikipedia [2], 4 atoms of hydrogen combine to produce 26.7 MeV of energy. So the production of that 0.025 cubic meters of helium produces 26.7 MeV times Avogadro's Number of energy, which Google [3] conveniently converts to Joules for us without asking: 2.6 × 10e12 joules. Wikipedia [4] says annual hydrogen consumption was 15 million kilograms per year in 2000. Let's roll with that, because whynot. Helium's atomic mass is 4.003, let's just call it 4, so the number we just ran in Joules was for 4 grams. So we have to multiple that Joule count by 3,750,000,000, yielding 9.75 × 10e22Joules of excess energy to produce the world's helium use for 2000. Human energy consumption in 2000 (because why not stay consistent) was 117.687 petawatthours, which is 4.23 × 10e20 joules. So, to produce the amount of helium we used in 2000, if I've got all my numbers correct (and it's been a while, but the tools I'm using here handle units automatically so that's a plus for my chances of being right), would produce as a byproduct approximately ~230 times the amount of energy humans consumed in that year. That's actually enough energy to be a serious problem, even before we discuss the fact that it comes out as positrons and gamma rays. (And neutrinos, but that's not a problem.) In conclusion, we are not about to start producing helium from fusion, even if we could. [1]: http://www.wolframalpha.com/input/?i=volume+of+1+mole+of+helium+at+STP+in+cubic+meters http://www.wolframalpha.com/input/?i=volume+of+1+mole+of+hel... [2]: http://en.wikipedia.org/wiki/Star#Nuclear_fusion_reaction_pathways http://en.wikipedia.org/wiki/Star#Nuclear_fusion_reaction_pa... [3]: https://www.google.com/search?q=26.7+MeV+times+Avogadro's+number https://www.google.com/search?q=26.7+MeV+times+Avogadro's+nu... [4]: http://en.wikipedia.org/wiki/Helium http://en.wikipedia.org/wiki/Helium
- sliverstorm 13y ago
  we are not about to start producing helium from fusion I thought that was the whole goal of cold fusion research?
  - jerf 13y ago
    Sorry, I was not clear. We are not about to start producing commercially useful quantities of helium from fusion anytime soon. Yes, fusion may produce helium as a byproduct, but even if we could perfectly capture it, it won't be much compared to global usage for a long time. Too many positrons and gamma rays.
fixxer 13y ago
Till then, we can just skim it off nat gas. Thank you shale! Problem SOLVED!

by MAGZine 13y ago

Hydrogen is the Universe's most abundant element. Helium is a product of Hydrogen that has undergone fusion. We'll be able to manufacture Helium when Nuclear Fusion becomes a reality on Earth.

jerf 13y ago

I've pondered that before and realized it could be problematic, so hurray, you've finally prompted me to run the numbers. A fusion reaction that starts from 4 hydrogen atoms (with no neutrons) produces one atom of helium. Let's just ignore the fact that this is a very hard reaction to do, even by fusion standards, and let's just ignore how the energy comes out and deal with raw amounts. Let's produce 1 mole of helium, which according to Wolfram Alpha, is .025 cubic meters of helium at standard temperature and pressure [1]. To produce that mole of helium, we need 4 moles of hydrogen. According to Wikipedia [2], 4 atoms of hydrogen combine to produce 26.7 MeV of energy. So the production of that 0.025 cubic meters of helium produces 26.7 MeV times Avogadro's Number of energy, which Google [3] conveniently converts to Joules for us without asking: 2.6 × 10e12 joules. Wikipedia [4] says annual hydrogen consumption was 15 million kilograms per year in 2000. Let's roll with that, because whynot. Helium's atomic mass is 4.003, let's just call it 4, so the number we just ran in Joules was for 4 grams. So we have to multiple that Joule count by 3,750,000,000, yielding 9.75 × 10e22Joules of excess energy to produce the world's helium use for 2000. Human energy consumption in 2000 (because why not stay consistent) was 117.687 petawatthours, which is 4.23 × 10e20 joules. So, to produce the amount of helium we used in 2000, if I've got all my numbers correct (and it's been a while, but the tools I'm using here handle units automatically so that's a plus for my chances of being right), would produce as a byproduct approximately ~230 times the amount of energy humans consumed in that year. That's actually enough energy to be a serious problem, even before we discuss the fact that it comes out as positrons and gamma rays. (And neutrinos, but that's not a problem.) In conclusion, we are not about to start producing helium from fusion, even if we could. [1]: http://www.wolframalpha.com/input/?i=volume+of+1+mole+of+helium+at+STP+in+cubic+meters http://www.wolframalpha.com/input/?i=volume+of+1+mole+of+hel... [2]: http://en.wikipedia.org/wiki/Star#Nuclear_fusion_reaction_pathways http://en.wikipedia.org/wiki/Star#Nuclear_fusion_reaction_pa... [3]: https://www.google.com/search?q=26.7+MeV+times+Avogadro's+number https://www.google.com/search?q=26.7+MeV+times+Avogadro's+nu... [4]: http://en.wikipedia.org/wiki/Helium http://en.wikipedia.org/wiki/Helium

sliverstorm 13y ago
we are not about to start producing helium from fusion I thought that was the whole goal of cold fusion research?
- jerf 13y ago
  Sorry, I was not clear. We are not about to start producing commercially useful quantities of helium from fusion anytime soon. Yes, fusion may produce helium as a byproduct, but even if we could perfectly capture it, it won't be much compared to global usage for a long time. Too many positrons and gamma rays.

fixxer 13y ago

Till then, we can just skim it off nat gas. Thank you shale! Problem SOLVED!