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China’s ‘Artificial Sun’ achieves fusion breakthrough

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

#191

Post by cc438 »

motoboi wrote: post #152
kybernetikos wrote: post #84

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…

> Massively abundant, cheap, clean energy should be one of humanity's top priorities. What about the big fusion reactor in the Sky? Shouldn't we go all in on solar? Why is so difficult to harness that source? Maybe the same obstacles make fusion so difficult to pursue.

Land utilization is the issue. The largest solar farms in the US requires an order of magnitude more land to produce the same amount of power as a relatively average nuclear plant.

The largest solar farm in the US, the Topaz Solar Farm in California, covers 25sq/km has a peak generation capacity of 550MW. The source uses the median of the 59 nuclear plants in the US to arrive at its 3.36sq/km (1.3sq/mile) per 1,000MW figure but the largest nuclear plant ever built, the Kashiwazaki-Kariwa plant in Japan, produces ~8MW on just 4.2sq/km of land which makes it twice as efficient in terms of land use as the median US plant.

That places solar at 13.75 sq/km per 1,000MW compared to nuclear's 0.525sq/km using the best case scenario for the density of existing sources. That doesn't even account for the variable output of the solar plant versus the consistency of nuclear generation. Solar is ultimately far too land hungry to ever serve as the world's primary source of electrity.

Source: http://www.nei.org/CorporateSite/media/filefolder/Policy/Pap...

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

#193

Post by sulam »

valarauca1 wrote: post #185
sulam wrote: post #179

Earlier quoted context omitted.

To save some people the click -- minimum warming potential by a few less-than-randomly selected sources: Coal: 770 Gas: 410 Rooftop solar: 26 Offshore wind: 8 Nuclear: 3.7 So, the word "vastly" above might be overstating things. Solar certainly isn't the most efficient, but it's pretty damn efficient compared to anything produced by biological processes.

400% and 700% are a vast difference. I'm not comparing Roof Top solar to Coal or Natural Gas yes very clear winner there. I'm comparing it to Hydro-Electric, Nuclear, Tidal, and Wind where it is by far the dirtiest.

You know, I edited out a sentence that read something like "unless you're playing statistical games with percentages" because I thought to myself that this was an unfair projection of what you might be thinking.

Thank you for making it clear that I was not being unfair, even in my pre-edited state.

They are a small difference compared to extractive mining. Statistics rhetorical tricks aside, the world would be much better off if we were using any mix of the non-extractive power technologies, even if that mix heavily weights rooftop solar.

Fundamentally the fact that rooftop solar is something I can put some money into tomorrow and see the results in six months means it is effective, which offends many people who would prefer that we spend our efforts in ineffective ways, either for ideological reasons (amusing that nuclear doesn't appeal to these types) or because they wish to maintain the status quo. Since the science shows that status quo is going to drown the island I live on inside of 75 years, I'm not a big fan of this point of view. My island is probably already dead, and the 80K people that live here need to find a new home in our or our children's lifetimes, but I am motivated to make choices that don't produce more stories like mine.

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

#194

Post by rodgerd »

kybernetikos wrote: post #84

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…

> 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.

You are. It's just not happening in the US, which has apparently decided that since coal was good enough for the 19th century, it's good enough for the 21st.

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

#195

Post by Paul-ish »

ars wrote: post #3

It's unfortunate that it's like this, but I automatically do not believe any scientific breakthroughs that come from China. There has simply been too much fraud for me to believe anything they say. http://www.sciencealert.com/80-of-the-data-in-chinese-clinic...

It is hard to fault people in that area of the world for turning to folk medicine with fraud rates that high. It is probably just as effective.

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

#196

Post by londons_explore »

cc438 wrote: post #191
motoboi wrote: post #152

Earlier quoted context omitted.

> Massively abundant, cheap, clean energy should be one of humanity's top priorities. What about the big fusion reactor in the Sky? Shouldn't we go all in on solar? Why is so difficult to harness that source? Maybe the same obstacles make fusion so difficult to pursue.

Land utilization is the issue. The largest solar farms in the US requires an order of magnitude more land to produce the same amount of power as a relatively average nuclear plant. The largest solar farm in the US, the Topaz Solar Farm in California, covers 25sq/km has a peak generation capacity of 550MW. The source uses the median of the 59 nuclear plants in the US to arrive at its 3.36sq/km (1.3sq/mile) per 1,000MW…

More importantly, with fusion, energy could become significantly cheaper allowing us to do things which weren't economically viable.

Make everything out of environmentally friendly, lighter and long lasting aluminium rather than steel + concrete.

Have street lighting that is as bright as sunlight over entire cities, allowing us to no longer be dependant on time of day.

Growing food crops indoors with artificial light, saving massive amounts of land.

Desalination to make all our water. No longer extracting it from rivers and aquifers. A cleaner, less polluted water source.

A single energy source - today we use petroleum (cars), natural gas (cooking and heating), electricity (lighting etc.), diesel (transport) and many more in industry. All of those need distribution networks. A single cheap energy source could coalesce a lot of infrastructure.

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

#197

Post by TheSpiceIsLife »

ufmace wrote: post #181
TheSpiceIsLife wrote: post #49

Earlier quoted context omitted.

What is the plan to extract energy from these things? Same old heat exchanger > supercritical steam > steam turbine > alternator? Or is there some way of getting electricity out of the plasma directly?

Yes. That also makes it difficult to scale up to energy production - now you need to route a bunch of cooling water plumbing and heat exchangers around it, engineer it to transfer the bulk of the reactor heat output to the cooling water without melting any heat exchangers, then build a turbine/generator rig to attach to it. Might possibly need an extra water loop too, depending on how much neutron flux ends up hittin…

The bulk of the reactor heat needs to stay in the reactor though, doesn't it? as that is essential in keeping the reaction going?

How does that affect the economics?

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

#198

Post by TheSpiceIsLife »

hx87 wrote: post #177
TheSpiceIsLife wrote: post #49

Earlier quoted context omitted.

What is the plan to extract energy from these things? Same old heat exchanger > supercritical steam > steam turbine > alternator? Or is there some way of getting electricity out of the plasma directly?

Fusion-heated gas turbines are certainly possible, so we may see combined cycle fusion power plants.

What is a fusion-heated gas turbines.

Combined-cycle gas turbines work by burning gas to spin a turbine and using the waste heat to create steam.

Where does the fusion heat come in to that cycle?

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

#199

Post by TheSpiceIsLife »

kobeya wrote: post #164
Gigablah wrote: post #109

Earlier quoted context omitted.

Sounds like a better track record than Theranos to me.

You are demonstrating awareness of the point being made: if scientific fraud was as rampant here as it is in China, Theranos wouldn't even be remarkable and still unknown. But it is in fact rare enough to cause scandal. If you want to keep that attitude and make non-contributory quips, go back to Reddit. It is not appreciated here.

Most of Big Pharma's medicines don't actually work.

As in, they don't work to cure the underlying condition. They work to treat the symptoms, and thereby require you to take the medicine fairly indefinitely if you want to by symptom free, side effects notwithstanding. Thereby extracting economic value from the generally unwell and ageing population and concentrating it in the hands of Big Pharma.

In that way I see most of medicine as being fraudulent.

Also, you're probably being down-voted for your last sentence, as it is, as you say not appreciated here.

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

#200

Post by philipkglass »

cc438 wrote: post #191
motoboi wrote: post #152

Earlier quoted context omitted.

> Massively abundant, cheap, clean energy should be one of humanity's top priorities. What about the big fusion reactor in the Sky? Shouldn't we go all in on solar? Why is so difficult to harness that source? Maybe the same obstacles make fusion so difficult to pursue.

Land utilization is the issue. The largest solar farms in the US requires an order of magnitude more land to produce the same amount of power as a relatively average nuclear plant. The largest solar farm in the US, the Topaz Solar Farm in California, covers 25sq/km has a peak generation capacity of 550MW. The source uses the median of the 59 nuclear plants in the US to arrive at its 3.36sq/km (1.3sq/mile) per 1,000MW…

Until recently the limiting factor on utility scale solar was high costs. Now intermittency looks like the most important constraint. Land availability is not the bottleneck for the US or most other countries. There are some countries that have a dense enough population and/or low enough insolation that land availability is a significant constraint on solar deployment (Japan, Taiwan, UK, Belgium...) but that's not common.

The real annualized power of the Topaz Solar Farm comes to 6 megawatts per square kilometer, using its 2015 generation total of 1,301,337 MWh. At that areal productivity[1], if you could ignore intermittency, it would take ~95,000 square kilometers to supply the 2013 US electricity demand of 4,986,400,000 MWh.

The US Corn Growers Association estimated that 27% of US corn grown in 2011 was for ethanol, and corn covered 92 million acres:

http://www.ethanolproducer.com/articles/8611/world-of-corn-r...

Converting 27% of 92 million acres to square kilometers, the US is using about 100,500 km^2 to produce ethanol.

But you can't ignore intermittency, so (barring much improved storage, which may happen but can't be assumed) solar PV is not a drop-in replacement for nuclear power.

[1]Other areas of the US get less sun than central California, but newer farms with more efficient panels and single axis tracking increase areal productivity significantly over the fixed-tilt CdTe construction of Topaz, so I think that 6 MW/km^2 is a reasonable number to use.

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