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MIT-designed project achieves major advance toward fusion energy

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Re: MIT-designed project achieves major advance toward fusion energy

#61

Post by causality0 »

dfdx wrote: post #34

Plenty of skepticism in these comments. I've been following CFS for a while and can present a point of view for why this time might be different. Fusion energy was actually making rapid progress in the latter half of the twentieth century, going from almost no power output in the fifties and sixties to a power output equal to 67% of input power with the JET reactor in 1997. By the eighties there was plenty of experim…

Are those calculations of net gain referring to the total energy generated, or the amount we can realistically capture and put to use?

Re: MIT-designed project achieves major advance toward fusion energy

#62

Post by OJFord »

anonuser123456 wrote: post #17
shmageggy wrote: post #7

These university press releases are always very positively framed. This one makes the new magnet seem incredibly promising and fusion seem like almost an inevitability now, but decades of failure have us conditioned for skepticism. What's the catch this time?

> What's the catch this time? This is D-T fusion. Which means you have to have T. Which currently comes from fission reactor and has a half life of 15 years. So the plan is to use a molten salt blanket with Be to breed T. But Be isn’t scalable for consumption, so maybe lead eventually. That’s probably do-able, it just slows down the rate new reactors can come online since Pb is not as good a neutron multiplier. Once…

> This is D-T fusion. Which means you have to have T.

For the other uninitiated, (or far enough out of secondary school and didn't take it further!) this seems to refer to Deuterium-Tritium fusion, D & T being the isotopes of hydrogen with an atomic mass of 2 (1 neutron, 'heavy' but stable) and 3 (2 neutrons, radioactive) respectively.

Re: MIT-designed project achieves major advance toward fusion energy

#63

Post by scythe »

speed_spread wrote: post #58
rnhmjoj wrote: post #50

Earlier quoted context omitted.

> But are they surmountable AND cheaper than existing nuclear or other energy sources? DT fusion solves the two biggest arguments that are always raised by nuclear energy opponents: storage of nuclear waste (it doesn't produce high-level waste) and safety (it's not perfect but it can't explode). I wouldn't call it a "meh", even if it comes off as much more expensive than fission.

It sounds like the T production chain might itself be quite messy. Molten isotopes salt and lead? How much of that stuff would you need? What do you do with when it goes bad? It may not go boom Chernobyl-style, but it's still far from the birds-in-the-sky deuterium-from-the-sea fusion dream.

The bad zone of radioactive byproducts is the half life between 10 and 1000000 years. Shorter and you can wait it out. Longer and the activity is low enough to ignore when it's spread out. When designing a fusion reactor, you can usually choose components that won't generate these undesirable nuclides. But in fission, many products are generated, so persistent contamination is practically impossible to avoid.

Re: MIT-designed project achieves major advance toward fusion energy

#64

Post by maccam94 »

dfdx wrote: post #54
zetalyrae wrote: post #49

Earlier quoted context omitted.

I've always wondered: why exactly is ITER so expensive, and slow? Is the engineering required at such a standard that it should takes decades of planning and construction and tens of billions of dollars? The timeline is so dilated (started in 1988, first plasma planned for 2025!) it feels like the kind of project that's expected to be cancelled from the start. It just doesn't strike me as obvious that reducing the ma…

Anecdotally, ITER was the largest of few options for a fusion researcher to run their experiment in a new tokamak. Everybody wanted to put their work into it, and as more features were added, the more funding it sucked up, leaving less money for other experiments, leading to more people wanting to put their experiment into ITER. Here's a presentation [0] that goes over why SPARC, being so much smaller and simpler tha…

This is also why it's exciting to see the huge drop in satellite launch costs driven by SpaceX. Your satellite design is going to be much different if you have a few chances to launch on a $1B rocket per year, vs launching it for $10M anytime. Rather than one complicated reliable one, you might make 10 simpler ones and buy extra flights to do repairs if necessary.

Re: MIT-designed project achieves major advance toward fusion energy

#65

Post by hutzlibu »

jcfrei wrote: post #20

Lots of negative comments in this thread. I've been following CFS for a few years now and I honestly believe this is an historic event - probably the beginning of the "fusion age".

"probably the beginning of the "fusion age"."

I wouldn't call it that, even if there would be a energy gain.

I call it beginning of "fusion age", when we solved fusion ad can build them reliable and reproducible - and if we still need them by that time, for main energy production.

Re: MIT-designed project achieves major advance toward fusion energy

#66

Post by AnimalMuppet »

ChrisMarshallNY wrote: post #6
dfdz wrote: post #2

The thumbnail of the youtube video made me laugh Smaller. Smarter. Sooner. 2018 Currently 2021 where is my fusion energy? But this time must be different, after this advance we are only a few years away from fusion energy?

The running joke has always been that “Fusion is 20 years away,” and has been, for the last 50 years. I really want this to work. I am a bit concerned, with how “the old guard” will react, once we have successful, productive, fusion. I foresee an astroturf NIMBY campaign against construction of fusion plants.

Per a comment by nielsbot, they're saying 2025. So, four years away, not 20. That's progress...

Re: MIT-designed project achieves major advance toward fusion energy

#67

Post by hutzlibu »

phicoh wrote: post #25
ChrisMarshallNY wrote: post #6

Earlier quoted context omitted.

The running joke has always been that “Fusion is 20 years away,” and has been, for the last 50 years. I really want this to work. I am a bit concerned, with how “the old guard” will react, once we have successful, productive, fusion. I foresee an astroturf NIMBY campaign against construction of fusion plants.

At the moment it is very far for clear that fusion will be cost effective. The article says this about the fuel of fusion: "The fuel used to create fusion energy comes from water, and “the Earth is full of water — it’s a nearly unlimited resource. [...]" They forgot to say that it is not the H2O that comes out of your tap. The earth is especially not full of tritium.

It's like saying the ocean is full of gold for anyone to pick up. It is. But not worth picking up with the very low concentration.

Re: MIT-designed project achieves major advance toward fusion energy

#68

Post by zardo »

noobermin wrote: post #24

University press releases need not be peer reviewed so they can get close to saying things that would offend other scientists and get away with it. The key phrase in "the most powerful magnetic field of its kind ever created on Earth" is "of its kind." Creating a many telsa magnetic field has been done in other experiments like with lasers[0], only they are physically smaller in size and last for nanoseconds, it's ju…

I think "it's kind" refers specifically to a magnet for plasma containment. As this doesn't set the record for a REBCO magnet.

https://nationalmaglab.org/news-events/news/lbc-project-worl...

Re: MIT-designed project achieves major advance toward fusion energy

#69

Post by neltnerb »

sbierwagen wrote: post #60
bigyikes wrote: post #56

Earlier quoted context omitted.

How do projects like LIGO ever get completed? I’m probably totally naive here, but I thought LIGO is physically larger and has many difficult constraints. The LHC comes to mind as well, and that absolutely dwarfs ITER in physical size. What’s the difference? Dealing with heat output? Superconductors are really hard maybe?

LIGO did take decades to construct, like the LHC. According to LIGO's wikipedia article, it was the most expensive project ever funded by the NSF in 1994.

LIGO's size is also deceptive, the legs are kilometers long but the design is an L with the important bit being to vibrationally isolate things, maintain dimensional stability, and maintain vacuum.

ITER is likely bigger in terms of volume of concrete or actual footprint.

Re: MIT-designed project achieves major advance toward fusion energy

#70

Post by rnhmjoj »

danans wrote: post #55
rnhmjoj wrote: post #50

Earlier quoted context omitted.

> But are they surmountable AND cheaper than existing nuclear or other energy sources? DT fusion solves the two biggest arguments that are always raised by nuclear energy opponents: storage of nuclear waste (it doesn't produce high-level waste) and safety (it's not perfect but it can't explode). I wouldn't call it a "meh", even if it comes off as much more expensive than fission.

> I wouldn't call it a "meh", even if it comes off as much more expensive than fission. It's not competing with fission, though. It's competing with renewables + storage + load shifting + efficiency. Compared to those, it might indeed be "meh".

Agreed, but grid and storage technology that will completely solve the renewable intermittence is probably as far in the future as commercial fusion reactors.
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