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MIT Inches Closer To ARC Reactor Despite Losing Federal Funding (computerworld.com)
Lucas123 writes: Experimenting with a fusion device over the past 20 years has edged MIT researchers to their final goal, creating a small and relatively inexpensive ARC reactor, three of which would produce enough energy to power a city the size of Boston. The lessons already learned from MIT's even current Alcator C-Mod fusion device — with a plasma radius of just 0.68 meters — have enabled researchers to publish a paper on a prototype ARC that would be the world's smallest fusion reactor but with the greatest magnetic force and energy output for its size. The ARC would require 50MW to run while putting out about 200MW of electricity to the grid. Key to MIT's ARC reactor would be the use of a "high-temperature" rare-earth barium copper oxide (REBCO) superconducting tape for its magnetic coils, which only need to be cooled to 100 Kelvin, which enables the use of abundant liquid nitrogen as a cooling agent. Other fusion reactors' superconducting coils must be cooled to 4 degrees Kelvin. While there remain hurdles to overcome, such as sustaining the fusion reaction long enough to achieve a net power return, building the ARC would only take 4 to 5 years and cost about $5 billion, compared to the International Thermonuclear Experimental Reactor (ITER), the world's largest tokamak fusion reactor due to go online and begin producing energy in 2027.
ARC is a very interesting scientific and engineering development project, but it is not a power generation facility. It is a demonstration experiment to learn how to run a fusion reactor with net energy production. There are still several major steps between ARC and a commercial electric generation facility.
With a box of scraps!
The nuclear waste problem IS solved. It's just that nobody wants to actually implement the solution.
You realize research isn't free, don't you? If you think fusion is a worthwhile goal, than the 5 billion isn't a waste.
We hope your rules and wisdom choke you / Now we are one in everlasting peace
Ah, the wonderful history of solutions for that.
"What do we do with all the lower-energy radioactive material leftovers?"
A little pool of water can store the waste from years of operation with less emissions than typical background radiation.
"That looks scary, what if something happens beyond anything you can design for?"
We have this modified reactor design that can get more energy out of the old fuel, it's not as good as fresh, but we can lower our output expectations a little and the remains of the fuel will be stable enough that you can carry them around in paper bags with negligible exposure.
"I read that someone could use that to make weapons, don't ever do that. Back to my last question."
Well, there is a mountain range that by all observation is tectonically stable, experiences very little erosion, is in the middle of nowhere, and could easily have a few vaults dug into it to store these leftovers for millenia.
"Harry Reid doesn't like that, you've been no help at all, we should just abandon nuclear energy completely!"
Scientific value != social value != economic value.
We can argue all we want about how interesting, promising, or (potentially) useful a research project may be. Or how much $$ should go to project X, and how much to project Y.
But whenever there's proper scientific research done, the money invested will yield a return: answers. Answers in terms of facts, measurement data, what works and what doesn't, perhaps even the odd conclusion about what seems best to try next. Some answers come cheap, some answers come only at great expense. Even if you find nothing: if you looked everywhere, properly, that means you now know there's nothing there, when before you could only guess what was there. Read: you still got answer(s).
Given the enormous size of the energy market, damage to our environment that's currently done as a result of extraction and burning of -mostly- fossil fuels, and huge benefits to mankind if cheap(er) energy sources were developed, imho we (as mankind) aren't spending nearly enough on fusion-related research. But hey that's just me.
And? People are ignorant, easily manipulated apes. I know I am. What makes the people of Nevada better equipped to know if a site is safe for nuclear storage than actual experts? Can they point to real fraud, cronyism, or any other proof that the site selection was faulty in any way other than "Waah! Nuclear power is scary!"? If so, then he wasn't doing his job.
Representative government is all about selecting somebody to govern for you, not to just be your mouthpiece. Sometimes they choose differently from what you would because they are better informed about the issue at hand. That's the whole freaking point!
Completely different class of magnetic fusion device. Completely different experiments.
Tokamaks are way simpler to build, but harder to operate than stellarators. ARC is an advanced tokamak design, and this one uses brand-new, state of the art superconductors to create a much more powerful containment field for the plasma. This machine, if built, will be used to study 'burning' plasmas, that is, plasmas getting most of their heating from thermonuclear reactions (as opposed to external heating). The research is needed, because we don't yet know what kind of exotic yet-unseen instabilities might be excited in a burning plasma.
Wendelstein 7-X is a stellarator; easier to operate, but FAR more complex to build. They don't perform as well as tokamaks, although they might be optimized in ways impossible in tokamaks. The Germans have the know-how and precision to build such an insanely complicated machine. This machine has superconducting magnet, and is the biggest stellarator to date. They want to get experience running a large stellarator with fully-superconducting magnets for long periods of time (shots running for many hours). In contrast, tokamak, like electrical transfomers, are inherently pulsed machines, and the shot times on most current machines are measured in seconds.