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opwieurposiu

Forget the power, 1.5GWt plant of this design could make almost 5 party balloons per hour worth of helium!

mev_per_fusion = 17.59e6

mev_per_j = 1.602e-19

pwr_thermal = 1.5e9

j_per_fusion = mev_per_fusion * mev_per_j

fusions_per_second = pwr_thermal/j_per_fusion

l_He_per_second = 22.4 * fusions_per_second / 6.02e23

l_per_ballon = 14.1

ballons_per_hr = (l_He_per_second * 60 * 60)/l_per_ballon

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I remember my dad saying about ten years ago that we should flatout stop selling helium to the average consumer until we've really cracked fusion. His reasoning was that helium is used in medicine and quantum computing, which has a whole slew of uses, vs a balloon that some kid is going to lose in five minutes anyway.

It would be pretty neat if we made helium a renewable resource, even if it is slow.

I'd say more helium is generated in the Earth crust than the potential fusion reactors powering all of humanity. Probably by several orders of magnitude.

Just distill it out of the atmosphere before it escapes into space - it'll be only a small order of magnitude more expensive than today's helium.

Forgive me for some ignorance here, since I know almost nothing about nuclear physics or chemistry, but from what I understood, doesn't helium escape out into space? Would there even be any to extract outta the atmosphere?

There is helium in the atmosphere. It is on its way from being created in the crust to escaping into space. But as long as it is in the atmosphere, it could be extracted.

You can make helium with fission, too - in fact that's where almost all of the helium on Earth comes from. Alpha radiation is just a helium nucleus, after all!

I know next to nothing about this. What material is being broken down to create helium?

I believe two hydrogens are fused together to create a helium.

Isn't it 4 hydrogens? And one of the cool things that happens is 2 of those protons turn into neutrons + positrons.

Fusing 4 protons into helium definitely happens in the sun, where protons are the most common hydrogen isotope. Most fusion on Earth is done using the deuterium-tritium reaction, which produces helium and a neutron. The reason is that it's an easier reaction to do: Obtaining the special hydrogen isotopes is much less of a pain than trying to design a reactor that uses the 4 proton reaction.

No, if I remember correctly the most probable fusion path are deuterium + tritium and deuterium + deuterium. In both case there are only 2 hydrogen isotopes fusing together, not 4.

There are lots of elements that decay by spitting out an alpha particle -- just another name for a helium nucleus.

I am reliably informed that spitting out an He+2 and turning into something chemically other is not fission. Apparently those unstable nuclei that split this way actually had a He nucleus bouncing around in there, and it tunneled out "honestly".

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