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Nuclear fusion has encountered a shortage of tritium

wired.co.uk

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Re: Nuclear fusion has encountered a shortage of tritium

#161

Post by ncmncm »

marcosdumay wrote: post #147
ncmncm wrote: post #109

Earlier quoted context omitted.

You could absorb neutron flux in a thousand tons of molten 6Li/7Li, and then try to separate grams of tritium from that thousand tons of molten, extremely inflammable metal, on a continuous basis. Good luck with that. Renewables do not incur such operating expenses. Put renewables and a fusion reactor on the grid, and fusion would never, ever win a bid. "Fusion .. will generate ... less ... than fission"? The whole d…

Hydrogen does not seem to dissolve very well in molten lithium. It is quite easy to separate on the lab, but yeah, the practical consequences of convection currents and putting it through a heat exchanger may change this. Anyway, I imagine the people studying fusion have an answer to this, since it only requires normal centuries-old chemical knowledge. I also do not believe fusion will ever be a competitive power sou…

Despite their fabled immiscibility, a few grams of oil would dissolve very thoroughly in a thousand tons of superheated water. The numbers matter.

The people studying fusion are carefully restricting their attention to the immediate problems of getting it to work at all. E.g., ITER will have no lithium blanket.

They figure on building another whole reactor to be completed (initially guessed) 15 years later at (initially guessed) 4x cost to begin tackling practical difficulties of extracting useful thermal energy.

Re: Nuclear fusion has encountered a shortage of tritium

#162

Post by john567 »

pfdietz wrote: post #158
john567 wrote: post #157

Earlier quoted context omitted.

See, now I know you're just lying because the equation isn't at all the same across all countries. Maybe you don't like nuclear and that's fine but you don't have to lie about it.

It remains the case that NPPs have never, anywhere, been built into a competitive market. They are only built when customers can be forced to pay for them.

So, what's your argument? That people won't buy nuclear energy on an open market or that an open market for nuclear energy doesn't exist?

In Sweden, where I live, about half of our electricity is from nuclear. It's built and operated by a state owned entity called Vattenfall and while they currently have a politically appointed board that is against nuclear they operate (for profit) all of our nuclear reactors. The only reason we don't build more is because they've made it practically impossible (not illegal) to expand nuclear energy through various political motivated decisions. Sweden had a referendum on the continuation of nuclear energy after the Chernobyl accident, we did vote, though by a narrow margin to transition away from nuclear. However, this past winter we had huge supply issues and people ended up having to pay 4x for electricity due to the premature shutdown of nuclear (meanwhile we had to power up oil and gas burning to compensate). Right now, most people in Sweden are of the opinion that we should keep our nuclear reactors. I, together with several others would like to us to expand our energy production from nuclear to prevent a reliance on oil and gas.

Re: Nuclear fusion has encountered a shortage of tritium

#163

Post by ncmncm »

john567 wrote: post #162
pfdietz wrote: post #158

Earlier quoted context omitted.

It remains the case that NPPs have never, anywhere, been built into a competitive market. They are only built when customers can be forced to pay for them.

So, what's your argument? That people won't buy nuclear energy on an open market or that an open market for nuclear energy doesn't exist? In Sweden, where I live, about half of our electricity is from nuclear. It's built and operated by a state owned entity called Vattenfall and while they currently have a politically appointed board that is against nuclear they operate (for profit) all of our nuclear reactors. The o…

> through various political motivated decisions

Politics is how policy is determined. People have tried other ways. Sometimes they worked. For a while.

Diverting money from building out renewables (and transmission lines) to build nukes ensures, at minimum, another decade of increasing reliance on oil and gas, and then paying more for power than you would have for renewables.

Re: Nuclear fusion has encountered a shortage of tritium

#164

Post by john567 »

ncmncm wrote: post #163
john567 wrote: post #162

Earlier quoted context omitted.

So, what's your argument? That people won't buy nuclear energy on an open market or that an open market for nuclear energy doesn't exist? In Sweden, where I live, about half of our electricity is from nuclear. It's built and operated by a state owned entity called Vattenfall and while they currently have a politically appointed board that is against nuclear they operate (for profit) all of our nuclear reactors. The o…

> through various political motivated decisions Politics is how policy is determined. People have tried other ways. Sometimes they worked. For a while. Diverting money from building out renewables (and transmission lines) to build nukes ensures, at minimum, another decade of increasing reliance on oil and gas, and then paying more for power than you would have for renewables.

Politics aimed at making a specific type of energy unprofitable by taxing it to death is not. It's activism.

Sweden cannot depend on solar alone, we have plenty of hydro in the northern parts of the country and wind doesn't work during winter. Wind also kills birds and insects, en masse.

People have an irrational fear towards nuclear. Fact is, very few people have died because of nuclear energy. If you compare deaths vs produced watts, nuclear is the single safest energy source by several orders of magnitudes.

Also, I don't know if that's a typo or a misunderstanding but we are not talking about nuclear weapons, i.e. nukes we are talking about thermonuclear energy production. These are two different things altogether.

Re: Nuclear fusion has encountered a shortage of tritium

#165

Post by pfdietz »

marcosdumay wrote: post #148
ASalazarMX wrote: post #140

Earlier quoted context omitted.

I dug more about this because it's an interesting topic. Basically we don't know how long a fusion generator will last before radioactivity forces its decommissioning because none exist yet, but fortunately it's short-life isotopes, about 50-120 years before they become safe. Orders of magnitude better than fission waste. I don't know about fusion vs renewables, because renewables are better, but they need a lot of n…

> Basically we don't know how long a fusion generator will last before radioactivity forces its decommissioning That was one of the main questions the ITER was supposed to answer, wasn't it? AFAIK earlier designs were quite short-lived, but some small changes fixed it. We will know how long they last as soon as we don't have an ITER anymore.

No, it wasn't. ITER uses materials (like CuCrZr) that are unsuitable for a production reactor, ITER will not perform tritium breeding (except in a few experimental modules that won't be sufficient to prove that technology), and ITER will only operate at full power on DT for at most a few weeks total over its lifespan.

Re: Nuclear fusion has encountered a shortage of tritium

#166

Post by pfdietz »

Stevvo wrote: post #94

One of the main objectives of ITER is to test Tritium Breeding technologies for DEMO. There is no shortage due to heavy water plants shutting down because it was never planes to use Tritium from that source in the first place!

ITER will not produce significant tritium, since most of its walls are not covered with breeding blankets. Most of the neutrons it produces from DT fusion will not hit a blanket module and therefore not breed tritium.

Re: Nuclear fusion has encountered a shortage of tritium

#167

Post by pfdietz »

tedd4u wrote: post #66
toomuchtodo wrote: post #39

Earlier quoted context omitted.

Roughly $50 billion has been spent globally on fusion research since the 1950s with nothing material to show for the effort; at what point do you stop throwing good money after bad? This strikes me as the learning from these posts.

I think you make an excellent point that fusion research is underfunded. NASA budget since the 50s is ~$1,400 billion — almost 30x what’s been put into fusion research. We’re asking fusion research to produce “free, clean, and carbon-free base-load electricity forever.” Seems worth a NASA-level of investment to me.

You could use the same logic to claim perpetual motion machine research is underfunded. The likelihood of the research leading to a useful result has to enter into it somehow.
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