Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

MIT-designed project achieves major advance toward fusion energy

news.mit.edu

Post reply on HN
Print view View original

191–200 of 438 posts

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

#191

Post by isoskeles »

mchusma wrote: post #112
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…

You are right, people who flippantly dismiss fusion just don't understand it. -Fusion has made consistent improvement, roughly in line with expectations for the level of investment (20 years away predictions were considering if we invested massively, which we did not). - Fusion is in theory something that could give us true energy abundance. Want to just desalinate water like crazy? Want to extract gigatons of carbon…

Imagine how much Bitcoin we could mine with that kind of energy source...

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

#192

Post by ncmncm »

sbierwagen wrote: post #59

Every mass-media article on fusion seems obliged to use "the fuel comes from water" line. I wonder if a "just says in mice" style harassment campaign would get journalists to stop saying this.

Journalists quote promoters. When something has no reasonable prospect of ever producing, promoters resort to lying. Journalists are not responsible for it, although experience should make them less credulous. But pie in the sky sells better than skepticism.

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

#193

Post by snek_case »

cletus wrote: post #87

I've long been skeptical of ITER making any sense given its insane cost. I mean even it succeeds, then what? Here's the truth: there's no such thing as free energy. Even if the fuel is so abundant it's actually or effectively free (eg deuterium), the energy isn't. Say it takes $50B to build a plant that produces 1GW of power, which I'll estimate at about 7TWh/year based on [1]. Let's also say it has a lifespan of 40…

Once we've shown this can work successfully, I think people will get excited and investment money will rush in. Ideally, we'll perfect the technology and make it cheaper and more efficient, just like any other technology. If an MIT-borne fusion startup IPOs and they have a working demonstration reactor, I would probably invest.

I think the hope is that with economies of scale, we could build really huge fusion plants one day, and drive down the cost of energy to less than a cent per KWh, and of course completely eliminate our dependency on fossil fuels. If energy becomes that cheap, we could use electricity to produce hydrocarbons from CO2 and water to power airplanes and such. Currently, we can imagine short-distance flights being electrically powered, but transatlantic flights are going to be difficult to achieve with batteries.

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

#194

Post by pfdietz »

gfodor wrote: post #142
pfdietz wrote: post #119

Earlier quoted context omitted.

DT fusion looks bad even if you totally ignore anything related to plasma physics or magnetic fields. Simply handling the heat flow and neutrons from the reactor looks to make the reactor too big to compete, compared to fission reactors. And then you have the problem of having to stick sophisticated stuff in the hot zone where hands-on maintenance is impossible (compared to a fission reactor, where just the fuel and…

Fusion doesn’t have the stigma of fission, or a lot of the risks, and so if we can get to a point where we are actually building new fusion reactors, we should assume the technology will improve rapidly.

It's a common error to think that fission power plants aren't being built because of "stigma". The actual problem is failed economics. Fusion promises to be even more expensive, for the reasons I explained.

It's not clear why one should expect fusion to have good experience effects. Fission didn't, and the non-nuclear parts of fusion power plants will be mature technologies.

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

#195

Post by derac »

SPARC is an amazing project. Congrats on this milestone! I am optimistic about SPARC and ARC. I'd love to hear legitimate critiques, though. I see a lot of negative comments on ITER, which is a very different situation. ITER will teach us a great deal btw, it isn't a waste of time.

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

#196

Post by ncmncm »

stjohnswarts wrote: post #144
ncmncm wrote: post #120

Earlier quoted context omitted.

ITER is a victim of a process seen frequently in large public-works projects, but particularly those where no one understands what anything really should cost, and where there is no practical deadline for completion. It is worst when there is no expected utility when it is done. We see it lately in the numerous military procurements (particularly the F-35 program), in NASA's SLS rocket, in California's bullet train t…

This sounds like a whole lot of speculation to me. Can you cite actual sources and documents that prove it?

You write like someone unfamiliar with the history of the other projects cited. Copious materials are readily found online. Read up on them. Try to identify any reason to imagine ITER is different. I will wait.

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

#197

Post by IntrepidWorm »

ncmncm wrote: post #186
IntrepidWorm wrote: post #154

Earlier quoted context omitted.

Citations? Or just idle theorizing?

It is the same process we see everywhere that massive cost overruns and unlimited delays manifest. Modern management methods can control cost and schedule where that is an actual goal. Where they don't demonstrates the actual goal. Every penny of cost overrun goes into some pocket. Smart management ensures many, many pocketholders are allied to keep the gravy train running.

Don't attribute to conspiracy what can be adiquately explained by beurocracy.

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

#198

Post by pfdietz »

apendleton wrote: post #177
pfdietz wrote: post #86

Earlier quoted context omitted.

Because the rest of the power plant will be similar (or also worse for fusion; consider the tritium handling facility or the robotic equipment for maintaining the fusion reactor). You would need a confinement structure, just to keep the tritium in (which will leak all over even in normal operation). So if you swap out a cheap PWR reactor for a much larger, and hence much more expensive, fusion reactor, you get a powe…

I guess I still just don't really see it... like, coal plants are also much less energy-dense than nuclear fission. So is solar, so is wind. We build all of those anyway. There are lots of things other than power density that contribute to whether or not a particular generation technology is economical. As to why massive fission reactors aren't built: there are plenty of already-available passively-safe/meltdown-proo…

Power (not energy) density matters in comparison of fission and fusion because the rest of the power plant is very similar. It's not relevant to the comparison of PV solar and fusion because this is not true. But we don't need to make that comparison, since we CAN compare those directly with fission by looking at actual costs, and then conclude they should be cheaper than fusion (because that will be more expensive than fission).

Tritium will be handled in such large quantities in a fusion reactor that even small leaks will be problematic. As I like to point out, the tritium made and burned in a 1 GW(e) DT fusion reactor in one year would contaminate 2 months of the entire flow of the Mississippi River above legal limits for drinking. Even small leaks could cause serious harm to property values (sorry, your ground water can't be drunk for the next 50 years.)

Gen-IV reactors aren't built not for political reasons, but because nuclear has become such an economic orphan that there aren't stakeholders to drive the construction of these things. The money isn't there because the ROI isn't there.

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

#199

Post by wsc981 »

isoskeles wrote: post #191
mchusma wrote: post #112

Earlier quoted context omitted.

You are right, people who flippantly dismiss fusion just don't understand it. -Fusion has made consistent improvement, roughly in line with expectations for the level of investment (20 years away predictions were considering if we invested massively, which we did not). - Fusion is in theory something that could give us true energy abundance. Want to just desalinate water like crazy? Want to extract gigatons of carbon…

Imagine how much Bitcoin we could mine with that kind of energy source...

> Imagine how much Bitcoin we could mine with that kind of energy source...

Not much more nor less, since the amount of Bitcoin generated every 10 minutes is controlled by an algorithm independent on how many machines are mining.

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

#200

Post by derac »

ncmncm wrote: post #120
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…

ITER is a victim of a process seen frequently in large public-works projects, but particularly those where no one understands what anything really should cost, and where there is no practical deadline for completion. It is worst when there is no expected utility when it is done. We see it lately in the numerous military procurements (particularly the F-35 program), in NASA's SLS rocket, in California's bullet train t…

Actually you can scale magnetic field stength or size to produce more power. SPARC (and later ARC) aims for the former with modern superconductor tech and is on track to potentially produce energy at Q~=11 by 2025.
Post reply on HN