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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.
"building the ARC would only take 4 to 5 years"
We all know this is at least 10 years out.
Do not argue with an idiot. He will drag you down to his level and beat you with experience.
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!
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
The world's smallest or largest [anything] will tend to have the most [any characteristic] and the least [any characteristic] for it's size.
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.
We are going to need portable fusion if we ever want to do serious interstellar travel. Wind power sucks in space, natural gas (combustion) takes up a lot of space and PV produces only a very slight bit of energy once you get a fair bit away from the sun.
Small fusion reactors can be superuseful even without taking into account space travel. From battleships to trains to large aircraft to small aircraft: they have a use at many scales where high energy density (production) is required or preferred.
MIT wants me to pay $28 to read this paper at Elsevier.
Is this how MIT plans to finance construction of the reactor?
It might be faster to borrow $5 billion from the Harvard endowment.
Oh wait, almost forgot that MIT has a $12 billion endowment,
yet they still want to nickel and dime the public.
Hey, MIT go fuck yourself.
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.