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ITER: World's largest nuclear fusion project begins assembly

bbc.co.uk

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Re: ITER: World's largest nuclear fusion project begins assembly

#361

Post by scottious »

gautamcgoel wrote: post #2

I think fusion is cool, but I also think it distracts from more important and promising approaches to clean power. No one has ever demonstrated a self-sustaining, net positive fusion reaction. It will probably take >30 years to make this technology cheap , safe and reliable and another >20 years to deploy it at scale. We don't have 50 years to wait on clean energy, we need it today. We should be focusing our attentio…

It's not an either/or... we should be pursuing lots of different avenues for power generation because we don't know what will pan out and what won't. Fusion might still be a huge win even if it takes 50 more years to perfect.

Re: ITER: World's largest nuclear fusion project begins assembly

#362

Post by pfdietz »

rini17 wrote: post #344
nucpal wrote: post #341

Earlier quoted context omitted.

That article is quite outdated, JET has 2020 D-T campaign. More importantly, fusion is a thousand times better than fission with respect to waste. No one is claiming there is no waste at all, but tritium has a half-life of 12.5 years so most of the waste will be safe within a few decades. The rest will largely be neutron embrittled steels/materials (classified as low level nuclear waste) that is easily stored. Compar…

So the waste output/power output is 1000 times better? Any sources pls? And this "Neutron embrittlement" does not create any dangerous long-lived isotopes? Like, we just wait few years and then normally landfill the concrete or how should I imagine the process?

Fusion creates much less long term radioactivity.

However, the mass of material contaminated with radioactivity is very high, since the radioactivity that is created is not concentrated in fuel elements, as it is in a fission reactor.

Re: ITER: World's largest nuclear fusion project begins assembly

#363

Post by read_if_gay_ »

sfifs wrote: post #216
cameldrv wrote: post #143

Earlier quoted context omitted.

I agree that costs are a major problem with nuclear. It seems to be a problem with all large scale construction projects in the past 20-30 years or so. On the safety tail risks, IMO it's more of a psychological/perception problem than a problem of actual risk. We've had a number of serious accidents in the history of nuclear power, and none of them have led to anything close to the death toll of a single year of runn…

The problem is actually that people are forced off of their homes, personal property and way if life should there be a big accident. For an average householder it's their life savings, friendships, community and way of life wiped out through no fault of theirs. Sure there'll be compensation and resettlement but who trusts governments to do this fairly and painlessly? It hasn't helped that no civilian nuclear operator…

> and this was expressly the reasoning that led Angela Merkel to reverse her stance

I know a lot of Germans who think that reversal was just opportunistic pandering to environmentalists to grab votes from the Green party.

Re: ITER: World's largest nuclear fusion project begins assembly

#364

Post by pfdietz »

nucpal wrote: post #346
pl-94 wrote: post #282

Can someone explain to me the advantages of fusion over fission? Except for the radioactive wastes and the enthusiasm of journalists I don't get it

It's mainly the waste. Nuclear fission is a stable source of energy that does not produce carbon emissions in production. It's pretty much the answer to the climate crisis except that it produces dangerous waste that is horrendous to store and manage. Fusion mainly avoids this :)

Fusion has been touted as avoiding waste and fuel availability problems of fission.

But the main problem of fission is that it's too damned expensive, with very large capital cost. Fusion makes this main problem worse, not better.

Re: ITER: World's largest nuclear fusion project begins assembly

#365

Post by pfdietz »

LockAndLol wrote: post #288

So many fusion sceptics in the comments that it sounds like a congregation of anti-vaxxers. Funding for fusion has been ridiculously low for decades and it's exactly because of sceptics with myopathy like the ones present here. Countries could've been pumping trillions into fusion and other clean energy, together, for years, but we'd rather vote for politicians willing to bomb the oil out of a poorer nation than thin…

The equation of fusion skeptics to anti-vaxxers is an unacceptable slur. We have excellent and incontrovertible evidence of the efficacy and value of vaccines. We have no evidence that fusion can be made practical, and there are well understood arguments for why it will not be.

Fusion is more like the Emperor's New Energy Source, an exercise in groupthink and sunk costing.

Re: ITER: World's largest nuclear fusion project begins assembly

#366

Post by throwanem »

The_rationalist wrote: post #305
lambdatronics wrote: post #261

Earlier quoted context omitted.

Tokamak-style reactors like ITER rely on a rapidly-changing magnetic field to induce an electric current in the plasma, for stability of the plasma. The magnet that provides this rapidly-changing field (the 'central solenoid') can't keep increasing in field strength indefinitely -- so there's a time limit to the life of the plasma. There are other ways to supplement the current in the plasma, which can help extend th…

But this is beyond ridiculous, so many years of R&D for 8 minutes of sustained acticivty activity? That sound like a joke

How long was the first powered flight?

Re: ITER: World's largest nuclear fusion project begins assembly

#367

Post by pfdietz »

666lumberjack wrote: post #357
pfdietz wrote: post #260

Earlier quoted context omitted.

https://model.energy/ Generally, low latitude places want more solar + batteries, high latitude ones want more wind + hydrogen. When optimizing with these four, plus nuclear, with the costs at that site, nuclear typically optimizes to 0%.

Using their data for the UK (2011 weather) and the 2020 technology scenario (rather than the projections which conveniently make renewables and storage significantly cheaper and Nuclear costs constant) and requiring that the system be carbon neutral it only takes very small tweaks to their assumptions to make Nuclear a clear winner. They are assuming by default that countries will be able to use salt caverns for hydr…

Europe has like 100x the salt cavern capacity needed. Hydrogen can also be stored in deep aquifers or hard rock caverns.

Using the 2030 data is proper, since any nuclear reactor we begin to build today won't be available until about then (which renewable and storage systems can be built in just a couple of years.)

Some of their cost figures are already too high, btw. Their 2030 estimate for the cost of electrolysers was 600 euro/kW; it's already down to half that (or even less, in China).

Re: ITER: World's largest nuclear fusion project begins assembly

#368

Post by hef19898 »

enaaem wrote: post #353
godelski wrote: post #154

Earlier quoted context omitted.

This is why I'm particularly upset about SSC's[0] failure to be built. There are many advantages to housing the smartest scientists in the world within the borders of your country, and those benefits aren't limited to scientific output. After all, a big part of these multi-national projects is the culture war. And let's be real, which is worth more? A super collider that runs for decades or the F35 (which cost more,…

I can actually argue for the F35. F35 and Carrier groups ensures open oceans and secure maritime trade for all. 90% of global trade is over the sea and is worth Trillions of dollars. There were times when countries would actively block maritime routes and steal cargo. A well integrated global economy, with open and secure maritime trade is beneficial for everyone and particularly the USA.

That would be done by frigates, destroyers and corvettes. Carrier groups are needed to dominate conflict theaters and other countries by projecting power.

Totally agree on open trade.

And as far as the F-35 is concerned, I think it was an attempt to be the end-all NATO, and global, fighter craft. Didn't work out that good, so far at least.

Re: ITER: World's largest nuclear fusion project begins assembly

#370

Post by willis936 »

pfdietz wrote: post #349
willis936 wrote: post #269

Earlier quoted context omitted.

You don’t speak for the people working on it, so your claim of sunk cost fallacy is null.

I am allowed to form my own opinion from the evidence we have. The evidence is that fusion is a huge boondoggle that is extremely unlikely to deliver anything useful. Asking people working in a field if it's promising is silly, since they are a biased sample. If they didn't think it was promising, they likely wouldn't be working in the field.

Indeed you are allowed to come to your own conclusions. I object to this statement.

>Fusion is an example of sunk cost thinking. The only reason we're working on it is because we had been.

This is putting forward the opinions of others. The premise is the people who stay in the field lacked some form of awareness of your arguments. They are aware and they disagree. You can’t assume your argument is accepted in the argument.

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