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These university press releases are always very positively framed. This one makes the new magnet seem incredibly promising and fusion seem like almost an inevit

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?

stormbrew 5y ago
I'm not sure it's possible for "lay people" (of which I am one) to recognize the difference between a very slow success and "decades of failure". Very little is invested into fusion power as a project, overall. So advancements seem to come when outside influences cause breakthroughs. I wonder how different the world would have been if it had for whatever reason been easier to produce fusion power than a fusion bomb. Military investment into the bomb would have probably pushed things forward a lot quicker. As is, the US military built thermonuclear bombs very quickly and then the appetite for advancement just dried up.
- fshbbdssbbgdd 5y ago
  You could say that military investment into fusion and fission bombs was groundwork for everything done since. On the other hand, the fact that nuclear power started with bombs probably contributed to it falling out of favor and being regulated to irrelevance (even though hydrocarbons have been responsible for a lot more deaths and environmental damage).
phkahler 5y ago
>> What's the catch this time? There are a bunch of issues still to be resolved. Higher magnet strength is/was just one of many.
- ncmncm 5y ago
  That the most expensive parts of the plant would be quickly destroyed by neutron irradiation is another. That it would cost overwhelmingly more than solar+storage is what will ultimately kill it. Someday. Many more $B will be spent first.
azalemeth 5y ago
Agreed. Whilst it may well be the largest, highest-field "only" high Tc superconductor design in the world, it's definitely not the highest-field high Tc superconducting magnet -- I believe that honour belongs to another bit of MIT with a 1.3 GHz NMR machine [1] (but I do remember something about Bruker collaborating with the US's National Magnet Lab and building a 30T machine -- I can't easily find a link). I really wish that press release would put the link to the paper at the top -- I found it very hard to work out what was actually new! [1] https://ieeexplore.ieee.org/document/6926794 https://ieeexplore.ieee.org/document/6926794
- bb88 5y ago
  This was a 32T field created, not sure if it's the same, but similar. https://english.cas.cn/newsroom/research_news/tech/201912/t20191209_227468.shtml https://english.cas.cn/newsroom/research_news/tech/201912/t2... Googling "30T magnetic field" shows some papers that have apparently "pulsed" 30T.
- maccam94 5y ago
  The magnet with the strongest magnetic field isn't necessarily the best engineering solution for a fusion reactor. In particular, these magnets need to be cooled (plumbing can be bulky and coolant can be difficult to work with) and allow for easy servicing of the reactor components (particularly the vacuum vessel which will need replacing every ~10 years due to neutron embrittlement). This magnet design is noteworthy because of several factors: high-temperature superconductivity means they're cheaper and easier to cool, the high field strength allows for a smaller scale reactor, and the physical construction of the magnets makes them cheap to build and allows for easy disassembly during maintenance periods.
- baking 5y ago
  That paper refers to a different magnet. The press release refers to milestone that was achieved a few days ago and has not yet been published. Their goal announced three years ago was to build the magnet and demo it this Summer. Let's just say they squeaked in under the wire since traditionally Summer ends in the US on the first Monday of September. (Unless you want to go with the equinox.)
anonuser123456 5y ago
> 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 they breed extra T, they have to capture and refine it. Hydrogen is very corrosive and hard to work with… and T is radioactive hydrogen. Again, probably doable. But guess what? Refining spent nuclear waste in fission reactors is also do-able. It’s also super expensive. And they still need a containment vessel that will withstand the wear and tear from sitting next to a mini hydrogen bomb all day. These challenges are likely all surmountable. But are they surmountable AND cheaper than existing nuclear or other energy sources? Meh?
- rnhmjoj 5y ago
  > 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.
  - danans 5y ago
    > 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".
    - rnhmjoj 5y ago
      Agreed, but grid and storage technology that will completely solve the renewable intermittence is probably as far in the future as commercial fusion reactors.
      - 5y ago
deleted 5y ago
[deleted]
apendleton 5y ago
I think the framing of what's happened so far as "failure" is probably the main thing responsible for this perception. It's true that progress has been slower than many had hoped and the most optimistic had projected, but "failure" sort suggests that the things the research community have been trying haven't represented meaningful progress towards the goal of power production, which isn't the case. Q (the ratio of energy out to energy in) has improved by about four orders of magnitude since controlled fusion was first achieved, and it's been a slow, at least reasonably steady march since the middle of the 20th century to achieve that progress. The current record-holding Q for magnetic confinement is around 0.67, so we need well under one more order of magnitude to get to the point of "theoretical break-even" (Q>1) -- we're most of the way there. A plant just barely better than break-even probably wouldn't be commercially viable, though, and while estimates vary, that point is probably somewhere in the 10-30 range, so we have maybe another order of magnitude to go after break-even. I don't think there's anything to suggest that after decades of progress we'll suddenly stop being able to make more. It's true that things have slowed down somewhat in the last 10-15 years, but most of the blame there goes to the need, in order to continue moving forward, to build bigger and bigger reactors, and the need to divert resources to that goal (mostly ITER). To the extent that promises of going faster have turned out to be hot air, it seems like they've mostly been in the form of novel approaches that do fusion in some fundamental new way that avoids the need to build an ITER-like thing. These approaches seem to often involve lots of unknowns, and end up getting bogged down in practical issues once they're actually tried (surprise plasma instabilities and so on). Recent advances in materials science (mostly REBCO magnets) and computing, though, offer a path to progress on the regular, bog-standard flavor of magnetic confinement fusion (tokamaks) on a smaller scale -- that's what this is. The nice thing about that is that the plasma physics here are very well understood, and have been heavily researched using conventional/not-super-conducting magnets that won't ever achieve break-even, but create identical plasma conditions inside the reactor (MIT Alcator C-Mod is effectively the conventional-magnet predecessor to this project). Up until now, the only real question was whether or not they could build strong-enough REBCO magnets, and now they have, so this is all good news and reason for optimism. Of course, commercial viability is a whole other question involving lots of questions besides physics. But the physics here seem to not be in serious doubt, unlike some of the proposals from other startups that are more exotic.

stormbrew 5y ago

I'm not sure it's possible for "lay people" (of which I am one) to recognize the difference between a very slow success and "decades of failure". Very little is invested into fusion power as a project, overall. So advancements seem to come when outside influences cause breakthroughs. I wonder how different the world would have been if it had for whatever reason been easier to produce fusion power than a fusion bomb. Military investment into the bomb would have probably pushed things forward a lot quicker. As is, the US military built thermonuclear bombs very quickly and then the appetite for advancement just dried up.

fshbbdssbbgdd 5y ago
You could say that military investment into fusion and fission bombs was groundwork for everything done since. On the other hand, the fact that nuclear power started with bombs probably contributed to it falling out of favor and being regulated to irrelevance (even though hydrocarbons have been responsible for a lot more deaths and environmental damage).

phkahler 5y ago

>> What's the catch this time? There are a bunch of issues still to be resolved. Higher magnet strength is/was just one of many.

ncmncm 5y ago
That the most expensive parts of the plant would be quickly destroyed by neutron irradiation is another. That it would cost overwhelmingly more than solar+storage is what will ultimately kill it. Someday. Many more $B will be spent first.

azalemeth 5y ago

Agreed. Whilst it may well be the largest, highest-field "only" high Tc superconductor design in the world, it's definitely not the highest-field high Tc superconducting magnet -- I believe that honour belongs to another bit of MIT with a 1.3 GHz NMR machine [1] (but I do remember something about Bruker collaborating with the US's National Magnet Lab and building a 30T machine -- I can't easily find a link). I really wish that press release would put the link to the paper at the top -- I found it very hard to work out what was actually new! [1] https://ieeexplore.ieee.org/document/6926794 https://ieeexplore.ieee.org/document/6926794

bb88 5y ago
This was a 32T field created, not sure if it's the same, but similar. https://english.cas.cn/newsroom/research_news/tech/201912/t20191209_227468.shtml https://english.cas.cn/newsroom/research_news/tech/201912/t2... Googling "30T magnetic field" shows some papers that have apparently "pulsed" 30T.
maccam94 5y ago
The magnet with the strongest magnetic field isn't necessarily the best engineering solution for a fusion reactor. In particular, these magnets need to be cooled (plumbing can be bulky and coolant can be difficult to work with) and allow for easy servicing of the reactor components (particularly the vacuum vessel which will need replacing every ~10 years due to neutron embrittlement). This magnet design is noteworthy because of several factors: high-temperature superconductivity means they're cheaper and easier to cool, the high field strength allows for a smaller scale reactor, and the physical construction of the magnets makes them cheap to build and allows for easy disassembly during maintenance periods.
baking 5y ago
That paper refers to a different magnet. The press release refers to milestone that was achieved a few days ago and has not yet been published. Their goal announced three years ago was to build the magnet and demo it this Summer. Let's just say they squeaked in under the wire since traditionally Summer ends in the US on the first Monday of September. (Unless you want to go with the equinox.)

anonuser123456 5y ago

> 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 they breed extra T, they have to capture and refine it. Hydrogen is very corrosive and hard to work with… and T is radioactive hydrogen. Again, probably doable. But guess what? Refining spent nuclear waste in fission reactors is also do-able. It’s also super expensive. And they still need a containment vessel that will withstand the wear and tear from sitting next to a mini hydrogen bomb all day. These challenges are likely all surmountable. But are they surmountable AND cheaper than existing nuclear or other energy sources? Meh?

rnhmjoj 5y ago
> 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.
- danans 5y ago
  > 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".
  - rnhmjoj 5y ago
    Agreed, but grid and storage technology that will completely solve the renewable intermittence is probably as far in the future as commercial fusion reactors.
    - 5y ago

deleted 5y ago

[deleted]

apendleton 5y ago

I think the framing of what's happened so far as "failure" is probably the main thing responsible for this perception. It's true that progress has been slower than many had hoped and the most optimistic had projected, but "failure" sort suggests that the things the research community have been trying haven't represented meaningful progress towards the goal of power production, which isn't the case. Q (the ratio of energy out to energy in) has improved by about four orders of magnitude since controlled fusion was first achieved, and it's been a slow, at least reasonably steady march since the middle of the 20th century to achieve that progress. The current record-holding Q for magnetic confinement is around 0.67, so we need well under one more order of magnitude to get to the point of "theoretical break-even" (Q>1) -- we're most of the way there. A plant just barely better than break-even probably wouldn't be commercially viable, though, and while estimates vary, that point is probably somewhere in the 10-30 range, so we have maybe another order of magnitude to go after break-even. I don't think there's anything to suggest that after decades of progress we'll suddenly stop being able to make more. It's true that things have slowed down somewhat in the last 10-15 years, but most of the blame there goes to the need, in order to continue moving forward, to build bigger and bigger reactors, and the need to divert resources to that goal (mostly ITER). To the extent that promises of going faster have turned out to be hot air, it seems like they've mostly been in the form of novel approaches that do fusion in some fundamental new way that avoids the need to build an ITER-like thing. These approaches seem to often involve lots of unknowns, and end up getting bogged down in practical issues once they're actually tried (surprise plasma instabilities and so on). Recent advances in materials science (mostly REBCO magnets) and computing, though, offer a path to progress on the regular, bog-standard flavor of magnetic confinement fusion (tokamaks) on a smaller scale -- that's what this is. The nice thing about that is that the plasma physics here are very well understood, and have been heavily researched using conventional/not-super-conducting magnets that won't ever achieve break-even, but create identical plasma conditions inside the reactor (MIT Alcator C-Mod is effectively the conventional-magnet predecessor to this project). Up until now, the only real question was whether or not they could build strong-enough REBCO magnets, and now they have, so this is all good news and reason for optimism. Of course, commercial viability is a whole other question involving lots of questions besides physics. But the physics here seem to not be in serious doubt, unlike some of the proposals from other startups that are more exotic.