
Using relativistic effects for laser fusion: A new approach for clean power - hsnewman
https://phys.org/news/2020-01-relativistic-effects-laser-fusion-approach.html
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PaulHoule
This bit is wrong: "The fuel for this method, which is usually a mix of the
hydrogen isotopes deuterium and tritium, is easier to obtain than uranium"

Uranium is relatively common and widely distributed, compared to oil.

It is possible to build a reactor that uses natural uranium

[https://en.wikipedia.org/wiki/CANDU_reactor](https://en.wikipedia.org/wiki/CANDU_reactor)

however the common LWR reactor uses mildly enriched uranium.

1 in about 6420 hydrogen atoms on Earth are deuterium, compare that to about 1
in 140 U atoms being the U235 which is used by current fission reactors.

So producing D requires isotope enrichment of an isotope which is much more
rare than U235, however, the enrichment is relatively easy to do because of
the huge mass difference between protium and deuterium.

Tritium has a half-life of 12 years, so like Plutonium 239 (half life 24,000
years) it doesn't exist in commercial quality in nature.

Like a fast breeder fuel cycle where neutrons are used to make Pu239 from
U238, a D-T fission reactor would need to breed T from lithium 6, then
fabricate it into targets with D.

Tritium is highly radioactive (short half life) and is hard to handle (it is
an isotope of hydrogen, hydrogen likes to go in between the atoms of metals,
and once tritium gets oxidized into water, you are not going to separate it,
the way you can remove many isotopes from Fukushima waste water.)

So it is not so clear that fussion is an environmental or safety win over
fission, particularly a fission fuel cycle that breeds Pu from U or U233 from
Th.

