Submitted by odyssey92 t3_zwkc6e in explainlikeimfive
CFDietCoke t1_j1v49q3 wrote
Not much. We have nuclear power already. Fission and fusion aren't all that different if you are just looking at them as power sources. Both have 0 carbon footprint. Both would be used to biol water to turn a steam turbine.
geeseherder0 t1_j1v6fgc wrote
Except for the spent nuclear fuel from fission…
CFDietCoke t1_j1v7v4i wrote
That's not really a concern. It's tiny amounts, we have ample places to put it, that is a political issue, not a science problem
reb390 t1_j1v78un wrote
This isn't really that accurate. Yes, both fission and fusion have zero carbon footprint and in the end will (at least in most cases) just boil water. Fusion however, if fully realized in its most ideal form, would allow us essentially turn seawater into fuel (so the source is basically limitless). Also fuel for fusion contains abot 100 times the energy per pound compared to fission. Finally, fusion has much less risk (but not zero risk) of danger from radioactive byproducts.
arcosapphire t1_j1v81m6 wrote
> Also fuel for fusion contains abot 100 times the energy per pound compared to fission.
Citation? I thought energy densities were pretty similar.
reb390 t1_j1v9y29 wrote
You can find it in this table on Wikipedia: https://en.m.wikipedia.org/wiki/Energy_density_Extended_Reference_Table Or at this site: https://epress.lib.uts.edu.au/student-journals/index.php/PAMR/article/download/1383/1464?inline=1#:~:text=Energy%20density%20of%20Deuterium%2Dtritium,reactants%20and%20products%20%5B1%5D.
The key detail is that pure uranium is only about 1/3 the energy density of Tritium-Deuterium but fission rods are only a couple percent U-235.
arcosapphire t1_j1vbzxn wrote
The chart shows 338 vs 86 TJ/kg for fusion vs breeder reactor. That's about 4x, not 100x. The U-235 is essential for the process but not the only source of energy in a fission chain reaction, which can convert U-238 to unstable plutonium.
However, as basically every fission reactor out there is a non-breeder reactor, I can see your point. If we count all the non-fissile parts of the fuel in the density equation (which is a debatable metric), then sure, the fuel density goes way down. But ultimately that isn't too relevant for figuring out the efficiency of the process overall.
CFDietCoke t1_j1v83xb wrote
> . Fusion however, if fully realized in its most ideal form, would allow us essentially turn seawater into fuel
Incorrect. Seawater is not H3 and cannot be fused.
reb390 t1_j1vajxr wrote
Seawater contains Deuterium (D) which can be used in a full cycle fusion reactor. Basically D+D creates either Tritium (T) + H or He3+ a neutron. Those products can then react with one another. The easiest reaction to do is D+T since it requires the lowest temperautures but Tritium needs to be manufactured which can be difficult.
DukeMikeIII t1_j1v7m4l wrote
Fission and fusion aren't that different, just opposites. One takes radioactive materials and splits an atom making more radioactive waste. Fusion starts with hydrogen, the most abundant element in the universe, and outputs helium. No long lasting radioactive waste and can produce a literal metric fuck ton more energy.
CFDietCoke t1_j1v7qur wrote
From an electrical grid perspective, not from "how it makes energy" perspective
And H3 is not the most abundant element in the universe.
DukeMikeIII t1_j1v80zt wrote
From an electrical grid perspective, wind and coal aren't that different.
CFDietCoke t1_j1v87qh wrote
Yes they are. Wind only generates power when the wind is blowing,. Coal has a carbon footprint per unit of electricity made.
DukeMikeIII t1_j1v8tqt wrote
The grid doesn't care about anything other than power. Wind only generates when there is air movement and coal only generates when it's burning.
ConstantThanks t1_j1v7n7i wrote
saying they are zero carbon footprint is not true. you have to factor in the mining of resources, building of the physical power plants, huge amounts of cement and steel, etc., backup power sources, all of the vehicles and other fossil fuel related activity used in maintenance, operation, construction, waste 'disposal,' etc. the only part of the process that's carbon neutral is the part that proponents of nuclear like to think about; the f(us,iss)ion.
CFDietCoke t1_j1v8eol wrote
> saying they are zero carbon footprint is not true
Fair point. I was specifically focusing on the reaction, but your point is a god one. However, the carbon footprint of building a reactor of any type can't really be avoided.
westbamm t1_j1v7ssg wrote
No buddy, without the risk of radiation, we can put them everywhere. That is huge.
CFDietCoke t1_j1v89ow wrote
There is ample storage that exists, today, for storing spent fuel rods.
westbamm t1_j1v9vuz wrote
Yeah, probably, don't touch it the next 1000 years and let's hope nature doesn't freak out. Ow, and not in my backyard please.
Ofcourse Fukushima and Chernobyl are unicorns, but why even risk it.
Nuclear is better than burning stuff, but fusion is even better.
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