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I have some hope for this approach, but as the article points out making reliable magnets is really the key. When a fusion reactor quenches, the plasma will bas
by ChuckMcM 6y ago
I have some hope for this approach, but as the article points out making reliable magnets is really the key. When a fusion reactor quenches, the plasma will basically eat the reactor through "hole" in the field. I keep hoping an effort to manufacture ReBCo coils directly will be successful, it would both make them less expensive and likely more reliable. However I expect it would require something like a 5-axis 3D printer capability.
Lastly, fusion power is one of the possible 'good' future events (unlike climate change, or nuclear war) that give me hope for the future of the planet.
- Florin_Andrei 6y agoControlled fusion seems one of the few awesome future things that's unambiguously good.
- technofiend 6y agoParticularly if there's some way to capture carbon that's otherwise impractical due to energy requirements.
- adrianN 6y agoFusion power will likely not be significantly cheaper than solar and wind for this purpose. Fusion plants are probably quite expensive and won't have an infinite lifetime. The big benefit is that you don't need batteries, but that doesn't matter if you want to use the power for carbon capture.
- pfdietz 6y agoWhy is is unambiguously good? There's great reason to doubt it could be anywhere close to economically competitive. That makes its value pretty ambiguous, in my view.
- ChuckMcM 6y agoI think that an argument can be made that it will always be economically competitive. That reasoning includes the 'fuel cycle' is non-waste producing, the economics of other energy sources continues to rise thus creating a wider window for economic recovery, the liability associated with fusion will always be less than the liability associated with fission, and as the carbon externalizations of fossil fuel are priced into its production it will become in-economic as well. Well designed fusion power should come in at or below hydro-electric power without the environmental impacts or risks associated with dams.
- pfdietz 6y agoThis is a bad argument. The fuel cycle is a small fraction of the cost of fission power. The main cost is the cost of building the plant. Fusion reactors will be much larger than and much more complex than fission reactors, per unit of thermal power output, so they should be more expensive. Fission reactors today are uncompetitive, even with liability artificially set to a small value, so that argument fails too.
- deleted 6y ago[deleted]
- reissbaker 6y agoThe reason nuclear fission is uncompetitive is its high operating costs. The cost to build the plant is a sunk cost: if the reactor is expected to be reasonably profitable to operate, you can fund building it. If the reactor is not expected to be reasonably profitable to operate... Good luck. That's what fusion aims to solve. The fuel is plentiful and you can easily buy it; the same can't be said of uranium. It's also much safer to run than fission, and produces vastly less dangerous waste. Perhaps your argument is that solar and wind are sufficient to power humanity's needs, without fission or fusion. That's debatable. But compared to fission, fusion is theoretically better on some pretty critical metrics — if we knew how to build a fusion reactor, which we don't yet. If you assume solar and wind won't be sufficient, fusion seems worth research.
- 6y ago
- why_Mr_Anderson 6y agoYou are right, in short term, fusion has not much value. But in (very) long term, unlike fission, which no matter how incredible it is, is still only 'planetary-level tech', fusion is the first 'stellar-level tech' we've unlocked so far. If we ever plan to go somewhere else than Solar system, fusion is the key.
- pfdietz 6y agoBeamed power will likely be much more practical for interstellar missions, or even large activities in the outer solar system. In particular, beamed power minimizes entropy generation at the target (and can even actively cool the target), which is vital for high thrust at high Isp.
- dmos62 6y agoMolten salt reactors and thorium fission is pretty exciting too.
- pfdietz 6y agoMaking reliable magnets is A key, but it's by no means the only one. Fusion faces many grave obstacles even if the magnets were totally reliable and cost nothing.
- thewarrior 6y agoWhat are some of the others ? I’ve heard even if everything worked the generated neutrons would eventually destroy the reactor.
- pfdietz 6y agoThat's one. Another showstopper is that all the energy has to be radiated through the wall of the reactor. By limits on this areal power density and the square cube law, the volumetric power density of fusion reactors will suck. Compare ITER (0.05 MW/m^3) or ARC (0.5 MW/m^3) vs. a commercial PWR fission reactor primary reactor vessel (20 MW/m^3). Stronger magnets don't save a reactor from this. The large size and complexity of a fusion reactor also means their reliability is a huge problem. There are many parts and joins there, and the machine will be so radioactive hands on access will be impossible. A single leak of coolant into the vacuum chamber renders a fusion reactor inoperable (while a fission reactor can keep operating even with multiple fuel rod leaks.)
- thewarrior 6y agoI’ve heard the sun has a very low power density it’s just that it’s massive. Maybe it’s just easier to create a star and live in orbit around it