Live data from Hacker News

China’s ‘Artificial Sun’ achieves fusion breakthrough

en.people.cn

121–130 of 235 posts

Re: China’s ‘Artificial Sun’ achieves fusion breakthrough

#121

Earlier quoted context omitted.

There was a reddit AMA in 2011 where a guy went to China and got stem cell treatments for his paralysis[1] and could walk now. Nobody on Reddit believed him. They basically spent the whole AMA trying to tell him it didn't happen. Then America did it 2016 and everyone was like "The Future is here and we did it first!"[2]. No, the future is already here, it's just not evenly distributed, or maybe it's already happening…

We do tend to diminish achievements from Asia historically. They discovered America first (the whole notion of "discovering" first a place where there already are people is absurd), they got printing first, they mastered gunpowder first... and yet most westerners will name Columbus, Gutenberg, and Europe.

>We do tend to diminish achievements from Asia historically

Except Japan, Singapore, Hong Kong, Taiwan and Korea. I think a healthy skepticism of China is warranted. Especially a People's Daily article. The newspaper that was a driving force during the Cultural Revolution.

https://en.wikipedia.org/wiki/People%27s_Daily

Re: China’s ‘Artificial Sun’ achieves fusion breakthrough

#122
post #92

I would love to see a huge effort towards fusion, on the same (or even greater) scale as the Manhattan project or the Apollo program. I had been disappointed in the way that fusion always seemed to be 30 years away no matter how many years went past, but I just assumed that that was because the science was hard and just the way it had to be. https://i.imgur.com/sjH5r.jpg https://www.21stcenturysciencetech.com/Article…

This might sound a bit like a buzz-kill, but I don't think fusion power is necessarily competitively cheap. I think it will be comparable to nuclear power with a ~ 10 times higher capital investment to build a fusion-plant. Already now solar is said to be cheaper then nuclear. But nevertheless humanity should explore fusion since it is more or less the only significant power source not (indrectly) depending on the su…

NO... humanity should explore fusion because we might desperately need it to survive.

To what amount can you scale up solar in a particular region?!

Yeah, I know, we're into low-power everything nowadays... but let's say that you end up with a desperate need for smth like 1 TW of power for something like a sea-water desalination plant, massive irrigation needs because climate change fucked you up, or building a huge set of flood barriers (think what Nederlands has now, but you need them 100x larger, 5x cheaper and done FAST) because sea levels rose and people will die if you don't get the massive cheap energy needs for these projects ASAP. Or maybe a huge TW power laser for some space-dev project if you don't want to think of disasters. Or maybe to decontaminate large amounts of water/soil/air after the first large-ish nuclear/bio/chemical war that will take place on Earth.

If you're betting on solar and wind and you end up suddenly needing high levels of cheap (it can be "long-term like 100 years on cheap" if you're a country with a good credit score) power, you're.... fucked! Yeah, fusion won't be scalable to massive energy needs "out of the lab", but in 100 years from now when your grandchildren will need it to save their lives from the consequences of our planetary fuck-ups, it will be!

(And yeah, short term you can scale fission better probably. So investment into "dirt-cheap fission power that anyone can have" is also crucial. But longer term it hits other scalability bounds.).

In a perfect world where we don't totally fuck-up the planet, solar and hydro and geotermal and wind and waves would be enough.

In the real world, where we will fuck-up the planet, things like fusion are desperately needed to un-fuck regions of it and re-terraform them (and also to get into space exploration fast and big, not "snail-paced solar-powered").

Re: China’s ‘Artificial Sun’ achieves fusion breakthrough

#123

Earlier quoted context omitted.

The very high cost of fission has a lot to do with how nasty, awkward, long-lasting and expensive the fuel and waste are. We really won't know until we try building a power plant.

Fusion produces energetic neutrons, and energetic neutrons are a very good way to make things radioactive. So all the popular approaches create waste that is more radioactive than fission waste, and probably comparable in volume. The only up side is that the decay products have a shorter half life. So the waste will only be a problem for a century or so, instead of for millennia. This may be better than fission, but…

Not really, fusion needs to keep the reaction in a near vacuum where fission uses a multi loop system which creates a lot more surface area and waste. Further the blanket needs to be made from lithium to make tritium in a DT fusion setup capturing those fast neutrons without creating long term waste.

Most importantly they are vastly safer and thus need far less security and far less insurance. Remember a huge benefit for PV solar and wind is they don't need guards.

PS: Another consideration is the half life is short enough that over 20 years things become a lot less radioactive. Fission has some half lives just long enough to be a real pain.

Re: China’s ‘Artificial Sun’ achieves fusion breakthrough

#124
post #4

Anyone remember that really old game Outpost? It ran on Windows 3.1; used a CD recording of The Planets as its soundtrack. That's the first time I've heard of Tokamak reactors. What these are trying to achieve is pretty amazing. I hope one day, one of these reactors will be able to sustain a greater output than input. It has the potential to move the planet into a completely different energy age. Imagine if we could…

I remember that game! Mini black hole starts gobbling up planet Earth. :) And the voxels.

You're thinking of Outcast (aka Infogrames Outcast).

Re: China’s ‘Artificial Sun’ achieves fusion breakthrough

#125

Earlier quoted context omitted.

There was a reddit AMA in 2011 where a guy went to China and got stem cell treatments for his paralysis[1] and could walk now. Nobody on Reddit believed him. They basically spent the whole AMA trying to tell him it didn't happen. Then America did it 2016 and everyone was like "The Future is here and we did it first!"[2]. No, the future is already here, it's just not evenly distributed, or maybe it's already happening…

We do tend to diminish achievements from Asia historically. They discovered America first (the whole notion of "discovering" first a place where there already are people is absurd), they got printing first, they mastered gunpowder first... and yet most westerners will name Columbus, Gutenberg, and Europe.

The whole notion of "discovering" first a place where there already are people is not absurd.

You discover that this continent exist from your point of view. There were people already living there but they were totally ignorant of where they were living, in fact most of them were in Stone or bronze's age.

"they got printing first, they mastered gunpowder first" Nobody will tell you this ever(that they got printing first). They will tell you that printing in metal last hundreds of times more than printing in porcelain or wood, and making it possible was a significant contribution that changed the world. How much typography do you see done today in porcelain? I have seen wood printing in China as an an art form, but not as something serious.

Gunpower was mastered by Europe with the invention of gunpower without fumes of course, that is absolutely true. You should try yourself a weapon done with black gunpower to see the difference. It happened in Europe because of the scientific revolution that happened only in Europe because of the Gutenberg press among other things. Not just that but dynamite, TNT...

The reality is that Asia created achievements until XV century, but they remained stagnant for 4 or 5 centuries. This is not something that I say, it is something that any Chinese will tell you.

Re: China’s ‘Artificial Sun’ achieves fusion breakthrough

#126

Earlier quoted context omitted.

The very high cost of fission has a lot to do with how nasty, awkward, long-lasting and expensive the fuel and waste are. We really won't know until we try building a power plant.

Fusion produces energetic neutrons, and energetic neutrons are a very good way to make things radioactive. So all the popular approaches create waste that is more radioactive than fission waste, and probably comparable in volume. The only up side is that the decay products have a shorter half life. So the waste will only be a problem for a century or so, instead of for millennia. This may be better than fission, but…

The advantage with Fusion is that you can control what elements are exposed to the neutron flux and so control what sort of new elements or isotopes you get. For instance there's basically nothing in the air except for dust that will absorb a neutron and turn into something you have to worry about. And part of the design of a fusion reactor is to use lithium to absorb as many neutrons as possible to breed tritium to feed back into the reaction.

By contrast the byproducts of a fission reaction are set by the fuels used and include really nasty stuff like Strontium-90 and so on. But even fission plants are designed so that the radioactive byproducts are essentially all spent fuel or things contaminated by spent fuel. Neutron activation is a design consideration rather than a source of waste.

Of course the neutron flux will tend to enbrittle the metals used in it's construction which will have the effect of increasing maintenance costs.

Re: China’s ‘Artificial Sun’ achieves fusion breakthrough

#127
post #92

Earlier quoted context omitted.

This might sound a bit like a buzz-kill, but I don't think fusion power is necessarily competitively cheap. I think it will be comparable to nuclear power with a ~ 10 times higher capital investment to build a fusion-plant. Already now solar is said to be cheaper then nuclear. But nevertheless humanity should explore fusion since it is more or less the only significant power source not (indrectly) depending on the su…

I agree - always been a bit mystified when fusion power is described as "cheap", fuel isn't a big component of the cost of fission power plants so even if the fuel is low cost it won't save you that much money. [I guess decommissioning costs might be lower but are they actually included in the costs of operating normal nuclear plants?]

The worst case scenarios for an accident at a fusion plant aren't nearly as bad as those at a fission plant so you should be able to get by with somewhat less in terms of paranoid safety measures and overbuilding.

Re: China’s ‘Artificial Sun’ achieves fusion breakthrough

#128
post #87

I would love to see a huge effort towards fusion, on the same (or even greater) scale as the Manhattan project or the Apollo program. I had been disappointed in the way that fusion always seemed to be 30 years away no matter how many years went past, but I just assumed that that was because the science was hard and just the way it had to be. https://i.imgur.com/sjH5r.jpg https://www.21stcenturysciencetech.com/Article…

Lets do a fusion kickstarter. All reward levels can be "carbon free energy".

Perks will be shipped in 30 years!

Re: China’s ‘Artificial Sun’ achieves fusion breakthrough

#129
post #92

Earlier quoted context omitted.

This might sound a bit like a buzz-kill, but I don't think fusion power is necessarily competitively cheap. I think it will be comparable to nuclear power with a ~ 10 times higher capital investment to build a fusion-plant. Already now solar is said to be cheaper then nuclear. But nevertheless humanity should explore fusion since it is more or less the only significant power source not (indrectly) depending on the su…

The very high cost of fission has a lot to do with how nasty, awkward, long-lasting and expensive the fuel and waste are. We really won't know until we try building a power plant.

Much of the nasty stuff comes from the fact that current (light water) reactors were actually meant to produce military plutonium. Bombs first. Energy was a by-product, and a very nice way to sell nuke-making to the civilians.

There is another way of doing fission, that was demonstrated (working prototype and all) in the 60's: molten salt. You basically dissolve the fissile matter in molten salt, provide initial heat, and you have a reaction going. This has multiple advantages:

- Originally designed for a nuclear plane, it is capable of reacting to load changes very quickly. It's basically easy to power-up, and easy to shut down.

- It is amenable to a passive security set up: when all goes wrong, the reactor shuts down by default. When it does, the radioactive matter is trapped in no-longer-molten salt, such that contamination is limited even if there is a leak.

- It consumes 90% of the fissile matter before it has to go to recycling. (Current reactors do about 10%.)

- It currently produces 5 times less waste than current reactors. There is hope to do even better.

- Last but not least, it can run off thorium, which is 4 times more abundant than uranium, and much better spread out geographically.

With one or two decades and a few billion dollars, we could make commercial grade reactors. They would almost certainly be significantly cleaner, and much safer than current light water reactors. They could adapt to changes of demand in the power grid, or compensate for the volatility of most renewable power sources without the need for a "battery miracle". Overall, they would make a terrific mid-term solution, that could last a couple centuries. More than enough time to come up with something better.

https://en.wikipedia.org/wiki/Molten_salt_reactor

Re: China’s ‘Artificial Sun’ achieves fusion breakthrough

#130
post #122
post #92

Earlier quoted context omitted.

This might sound a bit like a buzz-kill, but I don't think fusion power is necessarily competitively cheap. I think it will be comparable to nuclear power with a ~ 10 times higher capital investment to build a fusion-plant. Already now solar is said to be cheaper then nuclear. But nevertheless humanity should explore fusion since it is more or less the only significant power source not (indrectly) depending on the su…

NO... humanity should explore fusion because we might desperately need it to survive . To what amount can you scale up solar in a particular region?! Yeah, I know, we're into low-power everything nowadays... but let's say that you end up with a desperate need for smth like 1 TW of power for something like a sea-water desalination plant, massive irrigation needs because climate change fucked you up, or building a huge…

You don't need to scale up solar or wind in a particular region, you just transfer it from afar via HVDC. See: https://en.wikipedia.org/wiki/Desertec

Sure there's engineering challenges in that, but no more than some hypothetical case where we need an entire fusion plant in some locality right now.

Post reply on HN