More invested in nuclear fusion in last 12 months than past decade • Hacker News Board

Re: More invested in nuclear fusion in last 12 months than past decade

#431

Post by raverbashing » Sun, Jul 24, 2022, 9:26 AM UTC

troorl wrote: post #414

dignick wrote: post #381

Earlier quoted context omitted.

There are several problems with fission (probably fusion too) as I understand it: 1. Cost per MW compared to renewables (~$150 vs ~$40 and falling). Here in the UK the government is promising to subsidise this to make it viable. 2. Construction time - average is 10 years, we don’t have that long to wait. 3. Decommissioning is expensive and a long way in the future. Is that cost built into the cost per MW? How can we…

> Cost per MW compared to renewables (~$150 vs ~$40 and falling). Do you count in all the subsidies the renewables get from governments, including the production of the solar panels/wind mills, land ownership, utilities and all kinds of tax cuts and preferential treatment? In my country billionaires own massive solar farms and make tons of money at the expense of everyone else.

Oil has way more subsidies than renewables. By far

I'm rooting for billionaires to own more and more solar farms please. Let them buy more newspapers and "think-tanks"

Because I'd really like to live on that world where oil has no subsidies, occupies no land and it gets magically transported throught the country

Re: More invested in nuclear fusion in last 12 months than past decade

#432

Post by toxik » Sun, Jul 24, 2022, 9:30 AM UTC

cycomanic wrote: post #416

bratbag wrote: post #399

Earlier quoted context omitted.

Cost factor isn't as relevant as you think, as this is an apple's to oranges comparison. Renewables are too unreliable to act as baseline generation for a country. In the UK last year for example we had very little wind, so we had to ramp up our gas power output to make up for our shortages in renewables. We burned through much of our gas reserves before the Ukraine war started, because of Renewable power unreliabili…

Just repeating the baseline myth does not make it true. Nuclear does not compete with gas it competes with coal and renewables. It is often technically difficult but more importantly economically prohibitive to run nuclear as on demand sources. So for both renewables and nuclear you need some sort of storage or peakers. Moreover nuclear is not the beacon of reliability, Frances nuclear plants were running to only 60%…

Calling it a myth doesn’t make it a myth. Power companies have been saying exactly this for years: they need PLANNABLE power generation. Building 3x solar or wind plants means 3x volatility.

Re: More invested in nuclear fusion in last 12 months than past decade

#433

Post by ascar » Sun, Jul 24, 2022, 9:31 AM UTC

cycomanic wrote: post #418

jamesrom wrote: post #407

Earlier quoted context omitted.

> Construction time - average is 10 years, we don’t have that long to wait. This is a fallacy in two ways: 1. Scaling up nuclear projects will decrease construction time and cost. Efficiencies are found by with scale. 2. The opportunity cost of not starting nuclear projects now will surely be worse than attempting 100% renewables. The point is that we can invest in both.

> > Construction time - average is 10 years, we don’t have that long to wait. > This is a fallacy in two ways: > 1. Scaling up nuclear projects will decrease construction time and cost. Efficiencies are found by with scale. More than half of a nuclear plant is essentially the same as any large scale power plant (goal, gas...). The opportunity for reducing cost through economies of scales is low. Economies of scales w…

> It's the other way around, the actual cost of building nuclear instead of much cheaper and faster renewables causes an opportunity cost

That's under the assumption the available money, hardware and labor of ramping up solar and building nuclear plants directly competes with each other. That's a pretty strong assumption and I highly doubt there is a strong enough link between any of those three for your argument to have significant impact.

E.g. We should be able to drive rapid solar expansion with government money and subsidies while incentivcing big energy carriers to build nuclear plants.

Re: More invested in nuclear fusion in last 12 months than past decade

#434

Post by adrian_b » Sun, Jul 24, 2022, 9:32 AM UTC

mlindner wrote: post #377

acidburnNSA wrote: post #354

Earlier quoted context omitted.

No proliferation risk at all in a tritium fountain full of 14 MeV neutrons? Are you sure you know what you're talking about? These will all be guarded with pseudo military guns guards and gates just like fission, and monitored by the IAEA. As for radiological safety, see point about tritium. And google tritium leak nuclear plant for good measure. Youre right that there is less radioactivity in fusion plants, but mayb…

> No proliferation risk at all in a tritium fountain full of 14 MeV neutrons? Are you sure you know what you're talking about? If you're putting hunks of uranium inside a fusion pressure vessel it'd be really obvious. Tritium itself doesn't have proliferation risk. > These will all be guarded with pseudo military guns guards and gates just like fission, and monitored by the IAEA. No they won't. Because even if you cr…

It is completely premature to claim that the radioactivity will be "several orders of magnitude less".

The neutron flux produced by a fusion reactor will be much higher than in any fission reactor, and it must be absorbed in a shield, to produce heat, which will be the output of the fission reactor.

Choosing an appropriate material for the shield will minimize the quantity of radioactive material that is created per unit of output energy, but it is pretty certain that the radioactivity will not be "several orders of magnitude less".

The best that can be hoped is that it is possible to find a shield material that will produce only very small quantities of long-lived radioactive isotopes, so that, after a storage for not too many years, the radioactivity might decrease to be "several orders of magnitude less".

Nevertheless this remains to be demonstrated.

For example, any piece of steel present near a fusion reactor would produce copious amounts of cobalt 60, but that would decay to negligible radioactivity after a few hundreds years.

Moreover, to ensure the predicted low residual radioactivity, any shield material needs to be free of impurities, which even in very small quantities could produce dangerous radioactive isotopes.

The requirements for advanced purification will greatly increase the cost of the structural materials for fusion reactors. However this is not a new problem. Similar requirements are imposed on the structural materials for fission reactors, but the fusion reactors will not be any better from this point of view.

Re: More invested in nuclear fusion in last 12 months than past decade

#435

Post by ncmncm » Sun, Jul 24, 2022, 9:35 AM UTC

formerly_proven wrote: post #410

dignick wrote: post #381

Earlier quoted context omitted.

There are several problems with fission (probably fusion too) as I understand it: 1. Cost per MW compared to renewables (~$150 vs ~$40 and falling). Here in the UK the government is promising to subsidise this to make it viable. 2. Construction time - average is 10 years, we don’t have that long to wait. 3. Decommissioning is expensive and a long way in the future. Is that cost built into the cost per MW? How can we…

> 1. Cost per MW compared to renewables (~$150 vs ~$40 and falling). Here in the UK the government is promising to subsidise this to make it viable. You can't directly compare cost per generating capacity, because nuclear, gas, coal etc. are available according to schedule, while most renewables aren't. Adding storage around renewables to make them schedulable raises costs.

Raises cost, but it is still way below cost of nukes.

Re: More invested in nuclear fusion in last 12 months than past decade

#436

Post by ncmncm » Sun, Jul 24, 2022, 9:39 AM UTC

toxik wrote: post #432

cycomanic wrote: post #416

Earlier quoted context omitted.

Just repeating the baseline myth does not make it true. Nuclear does not compete with gas it competes with coal and renewables. It is often technically difficult but more importantly economically prohibitive to run nuclear as on demand sources. So for both renewables and nuclear you need some sort of storage or peakers. Moreover nuclear is not the beacon of reliability, Frances nuclear plants were running to only 60%…

Calling it a myth doesn’t make it a myth. Power companies have been saying exactly this for years: they need PLANNABLE power generation. Building 3x solar or wind plants means 3x volatility.

Building 3x renewables in widely distributed places radically reduces volatility.

Wind is always blowing somewhere. Sun is always out somewhere. Storage is transportable.

Re: More invested in nuclear fusion in last 12 months than past decade

#437

Post by johnchristopher » Sun, Jul 24, 2022, 9:44 AM UTC

smaudet wrote: post #365

johnchristopher wrote: post #362

Earlier quoted context omitted.

> It runs 24/7 on a tiny land and material footprint. Isn't that a myth though ? Nuclear plants have planned and unplanned maintenance downtime. They actually have enough of these in my country that it's deemed unreliable or as reliable as wind turbines (depends on who you ask).

I think tiny relative to a coal installation? I'm just guessing here, though, all nuclear facilities I have seen are fairly enormous, albeit their size is small compared to the number of required non-nuclear plants it would take to replace their energy output.

Obviously my comment is about service availability, not land surface.

Re: More invested in nuclear fusion in last 12 months than past decade

#438

Post by adrian_b » Sun, Jul 24, 2022, 9:46 AM UTC

shawn-butler wrote: post #357

acidburnNSA wrote: post #153

But where are the fusion neutrons? (See Voodoo Fusion [1]) [1] https://vixra.org/pdf/1812.0382v1.pdf I'm a professional fission guy. I started out in fusion and switched to advanced fission. These days I don't see why we don't just build lots more regular old LWR fission reactors. Imagining that somehow fusion is going to a) work, b) be cheap (fuel cost is only 5% of total nuclear fission cost so who cares), and c) n…

fusion has better marketing in the marketplace of the uninformed. "Harnesses the power of the sun" vs "nuclear bombs" I'm sure the greens will try and tear it down it if it ever comes to commercial viability and start calling it thermonuclear power or some nonsense.

Which is pretty much a complete lie, because the proton-proton and Bethe cycles that power the Sun and most stars will not be used in a fusion reactor, any time soon.

The fusion reactions that are likely to be used in the first fusion reactors are precisely the same as those used in the thermonuclear bombs, a.k.a. H-bombs.

Re: More invested in nuclear fusion in last 12 months than past decade

#439

Post by rmbyrro » Sun, Jul 24, 2022, 9:47 AM UTC

dignick wrote: post #381

acidburnNSA wrote: post #153

But where are the fusion neutrons? (See Voodoo Fusion [1]) [1] https://vixra.org/pdf/1812.0382v1.pdf I'm a professional fission guy. I started out in fusion and switched to advanced fission. These days I don't see why we don't just build lots more regular old LWR fission reactors. Imagining that somehow fusion is going to a) work, b) be cheap (fuel cost is only 5% of total nuclear fission cost so who cares), and c) n…

There are several problems with fission (probably fusion too) as I understand it: 1. Cost per MW compared to renewables (~$150 vs ~$40 and falling). Here in the UK the government is promising to subsidise this to make it viable. 2. Construction time - average is 10 years, we don’t have that long to wait. 3. Decommissioning is expensive and a long way in the future. Is that cost built into the cost per MW? How can we…

> Here in the UK the government is promising to subsidise this to make it viable.

Doesn't make it cheaper, only hides the cost. Subsidies are many times perversive. Prices are communicating something. When Gov messes with it, people and organizations tend to make bad decisions for themselves, society, environment or everything.

Re: More invested in nuclear fusion in last 12 months than past decade

#440

Post by ncmncm » Sun, Jul 24, 2022, 9:47 AM UTC

freemint wrote: post #401

Retric wrote: post #326

Earlier quoted context omitted.

The issue when you say let’s build X00 new LWR is just cost vs benefit. Something like 5 Trillion in additional nuclear subsidies might slow down climate change a low single digit percentage over the next 30 years. This relates not just to the high cost of nuclear but also the delay between deciding to build nuclear and actually getting low carbon energy from a nuclear reactor. Spend 1/4th that on solar or wind subsi…

500 is 1-(1-risk)^500 the risk

... which is much larger than 500x, approaching near-certainty, for any non-negligible value of unit risk.