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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

#161

Post by [deleted] »

ncmncm wrote: post #126
rnhmjoj wrote: post #70

Earlier quoted context omitted.

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

The only open question about large-scale energy storage is which of many viable alternatives will turn out cheapest, and when their price will bottom out. Battery storage that starts at 1/3 of lithium cost, before price begins to fall, is coming to market. Until prices do start to bottom out, investment in storage is wasteful, so dollars go to generating capacity of known utility. Each square meter of panel that goes…

[deleted]

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

#162

Post by vajrabum »

ncmncm wrote: post #143
pfdietz wrote: post #117

Earlier quoted context omitted.

> Fusion is what reduces energy cost potentially another 10x How did you arrive at that conclusion?

Anybody looking at numbers sees fusion never, ever producing so much as a single erg of commercially viable energy. So, anybody saying otherwise is simply making it up.

What numbers are those? Or perhaps you even have a citation from work done on the topic by reputable physicists?

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

#163

Post by ncmncm »

gfodor wrote: post #149
ncmncm wrote: post #139

Earlier quoted context omitted.

Since power from a fusion plant would cost 100x+ what solar and wind cost, no. But every cent diverted to fusion from solar brings climate disaster closer.

Do you have a reason to believe capital deployed to fusion would have been deployed to solar? And if so, why do you think it would make a difference, given the market feedback loop going on with solar driving down costs? Edit: also, your comments seem to be incredibly negative on fusion, would you mind disclosing if you have any solar or wind connected conflicts of interest?

I have no money invested in solar, wind, or storage enterprises. To my shame.

My beef with fusion is about long-term hucksterism and wholly-legal corruption. STS, SLS, F-35, Big Dig, 2nd Ave, Cal bullet train, fission, fusion.

Dollars are fungible. Would fusion dollars otherwise go to renewables build-out? They might be more likely to go to battery, solar panel, superconducting power transmission, or carbon reclamation research. All of those would be welcome alternatives.

Even FRC fusion would be a better use of funding.

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

#164

Post by baking »

sdeyerle wrote: post #10

In the original proposal for the ARC reactor, they were proposing making the magnet separable so the top and bottom of the reactor could be separated and the vacuum vessel removed. (See pg. 5 of https://library.psfc.mit.edu/catalog/reports/2010/15ja/15ja0... ) It doesn't look like they are targeting that here. Does anyone know if that is ARC (not SPARC) specific, or if that has been abandoned?

The demountable magnets for ARC are so the blanket and vacuum vessel can be swapped out as a whole unit for replacement during maintenance. SPARC has no blanket and will only be used for some thousands of ten second shots or the equivalent of a week or two of continuous operation. The magnets being unshielded will probably fail before the vacuum vessel does.

CFS will be building a lot more magnets, not only for SPARC but for other customers, physics experiments and medical equipment, so I expect they will be working on many additional features including demountable joints for ARC.

One of the early tests they did of the VIPER cable at the SULTAN test facility in Switzerland involved a joint formed by clamping the ends of two cables to a copper bar. It does show that resistive joints are possible with HTS cables, unlike LTS cables, but the actual configuration of a joint for a large magnet is obviously a different matter. Luckily they will have a few years to work on it.

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

#165

Post by anonuser123456 »

worldvoyageur wrote: post #94
anonuser123456 wrote: post #17

Earlier quoted context omitted.

> 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…

Tritium is a natural byproduct of CANDU fusion reactors, of which there are some 25 or so in operation globally, mostly in Canada. CANDUs use heavy water as a neutron moderator (D20 instead of H2O), making T2O a natural byproduct. Though most of the reactors do not harvest the tritium, a small number do. CANDU operators have long been ready to make the capital investments in tritium harvesting, once demand materializ…

I think the SPARC guys are going to eat all the CANDU tritium before ITER ever gets a chance light up.

If we have to scale up fission reactors to produce enough tritium to scale fusion reactors, then don't need the fusion reactors.

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

#166

Post by baking »

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 company was founded in 2018. At the time they promised to demo this magnet during the Summer of 2021. What is the issue?

The goal is to get fusion power om the grid in the 2030's and scale up in the 2040's. Stop moving the goalposts.

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

#167

Post by codesnik »

worldvoyageur wrote: post #94
anonuser123456 wrote: post #17

Earlier quoted context omitted.

> 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…

Tritium is a natural byproduct of CANDU fusion reactors, of which there are some 25 or so in operation globally, mostly in Canada. CANDUs use heavy water as a neutron moderator (D20 instead of H2O), making T2O a natural byproduct. Though most of the reactors do not harvest the tritium, a small number do. CANDU operators have long been ready to make the capital investments in tritium harvesting, once demand materializ…

(you probably meant to write "CANDU fission reactors")

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

#168

Post by apendleton »

eropple wrote: post #135
apendleton wrote: post #39

Earlier quoted context omitted.

The plan is for them to breed their own tritium, though, so the consumables coming in the front door would just be deuterium and lithium, both of which (while less common than tap water) are not rare.

My understanding (and I am a layman) is that lithium isn't that accessibly common on Earth, and that we're doing a bang-up job of using as much of it as we can get our hands on already. Are there practical methods of extracting less accessible lithium that don't themselves have nasty side effects?

Yeah, there have been rumblings about recovering it from seawater: https://electrek.co/2021/06/04/scientists-have-cost-effectiv...

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

#169

Post by mikepurvis »

mauvehaus wrote: post #158
mikepurvis wrote: post #121

Earlier quoted context omitted.

Arguably the Shuttle suffered from this too— instead of being a tightly focused space truck, it needed to be able to do ridiculous things like fly polar missions and grab Soviet spy satellites right out of the air.

Point of order: if the space shuttle were grabbing satellites out of the air, something has gone terribly wrong with both launching the satellite and the shuttle.

I think the idea was that early spy satellites would use film rather than digital transmission, so it would be at the very least necessary to potentially grab one's own satellites.

In any case, this exact question was asked here, and the top-rated response indicates that it's unlikely that the design requirement was ever meant to refer to grabbing an uncooperative payload:

https://space.stackexchange.com/questions/41741/was-the-spac...

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

#170

Post by redis_mlc »

crazygringo wrote: post #145
phscguy wrote: post #32

Earlier quoted context omitted.

Yeah, any positive news on fusion progress and there always seems to be the same set of comments appear that are overwhelmingly critical of fusion development. Fusion is not well funded and imo has been let down by mismanagement of ITER, and despite this keeps making progress. I feel that fusion is one of humanity's best shots at actively reversing climate change, and it is disheartening to see such widespread pessim…

> I feel that fusion is one of humanity's best shots at actively reversing climate change Couldn't the same thing be said about current fission reactors? I get that fusion doesn't have the downsides of fission... but I'm also worried that people will be "scared" of fusion in the same way they're against GMO vegetables and irradiated fruits, totally irrationally...

> they're against GMO vegetables and irradiated fruits, totally irrationally...

COVID-19 is GMO ... are you in favor of pandemics?

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