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If anyone was wondering if SPARC and ARC care about this, SPARC onsite tritium inventory is planned to be fairly low: just 10 grams (not kg) in this 2018 SPARC paper[0]. I would also speculate that 200 kg/year sounds a little bit too high, although I can't find an ARC paper to corroborate (the magic words you want are "total on-site tritium inventory"). [0] https://www1.psfc.mit.edu/research/alcator/pubs/APS/APS2018/…
Tell that to the Sun. We already have a fusion reactor sufficient to meet all of humanity's energy needs, it's a gravitationally contained fusion reactor with a projected lifetime of at least one billion years, so why not just rely on that? Seems to have done wonders for the biosphere for the last one billion years, hasn't it?
If the quantity of energy produced by nuclear fusion would remain negligible in comparison with the solar energy, then there is no need for it.
While on Earth using the nuclear fusion makes little sense, mastering it could enable the exploration and even the colonization of the Solar System.
> “It would be an absurdity to use dirty fission reactors to fuel ‘clean’ fusion reactors,” This seems like a non-sequitur. If we need to keep around (or even build) a few heavy-water fission plants to enable the fusion industry, what's the problem? The simple phrasing of fission as "dirty" really shows the quotee's biases. You could easily envision a stable energy mix with a few percent of fission, the rest fusion a…
- "a few heavy-water fission plants" It's actually tilted very far in the opposite direction. The ratio is something like 600:1 heavy-water fission to fusion. A mix of 99.8% fission and 0.2% fusion, if your fusion is relying on that as its sole source of tritium. - "Small quantities of tritium are also produced by CANDU-type nuclear reactors—on the order of 100 grams per year for a 600 MW reactor," https://www.iter.o…
Still, as I said originally, it sounds like keeping our current level of fission reactors around should solve the bootstrapping problem.
Tell that to the Sun. We already have a fusion reactor sufficient to meet all of humanity's energy needs, it's a gravitationally contained fusion reactor with a projected lifetime of at least one billion years, so why not just rely on that? Seems to have done wonders for the biosphere for the last one billion years, hasn't it?
Instead of asking oblique rhetorical questions, you could actually make a meaningful statement.
As far as making fusion reactors to boil hot fluids to drive steam turbine-generators to power the electrical grid... doesn't seem too likely. High-efficiency monocrystalline Si PV panel fabs would be a better investment.
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Or we could chose a number of WAY safer fission reactors for the same cost and same power output (Pick your favorite Gen IV reactor). We also don't end up creating a literal nuclear weapons manufacturing plant in every nation that wants to use this (since the "fuel" for this reactor is constantly detonating nukes).
Why not Gen III+, these are ready to go whereas most Gen IV reactors are still in the drawing board possibly early prototype phase.
Anything is better than the "drop a nuke in the hole" plan. Both Gen III+ and Gen IV reactors can hit the market before all the red tape is cut for prototyping the hole bomb.
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No shit. Turns out a daily detonation of a fusion bomb tends to wear on things and when those things fail... you've just detonated a fusion bomb.
They actually want to detonate a H-Bomb every 45 minutes, all day every day. 32 nuclear explosions every day. One does have to appreciate how these guys took anti-proliferation concerns with the nuclear industry and said "fuck it, everyone knows we're only doing this to make bombs, so lets make a shit ton of bombs". No more concerns about terrorists getting their hands on some yellowcake and making a dirty bomb. Now…
It's so widely impractical.
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Last week Elon explained that the problem of fusion is that it will be more expensive than solar and wind.
The real question is whether it's more expensive than solar/wind plus the batteries required for dispatchable power. The answer depends on the reactor design, which Elon doesn't know. There are a lot of possibilities, and if the first ones are too expensive, later ones might not be.
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The same line of reasoning says that we should build conventional light- or heavy-water reactors. The risk is minimal. And they're (a) tested and (b) much cheaper than PACER.
The advantage of a PACER setup is that you get a lot more bang (heh) per kg of uranium than you do out of a fission reactor. But the cost of uranium is not currently a problem with our fission reactors. We do have a problem with radioactive waste, but even that is way more political than it is technical. I wonder which two senators are going to be ok with detonating 32 bombs in their state every day? This isn't the 5…
ITAR should be shut down. Straight up. It's a complete waste of taxpayer funds taht holds no prospect of producing commercially viable power. Its design constraints were decided decades ago. Since then science and engineering has advanced a lot. I'd love if it fusion became commercially viable but I'm doubtful it ever will. At the least the kind involving fusion atoms in a plasma for all the documented reasons, most…
https://www.world-nuclear-news.org/Articles/ITER-tokamak-ass...
https://www.reuters.com/article/us-france-nuclear-fusion/ite...