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

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

#541
post #441

Earlier quoted context omitted.

>Honestly, I don't understand why we can't do both. Because we're been doing neither for 40 years.

And, money is fungible . A dollar spent on X is not spent on Y. This is not a difficult concept.

It seems to be, because there isn't a fixed amount of money.

Money isn't the problem. Manpower and materials are the problem.

Spending manpower and materials on X cannot be spent on Y. Manpower and materials are not fungible - at least not in the nuclear space where requirements are very high.

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

#542

Earlier quoted context omitted.

They've given up on fast reactors. Reprocessing with thermal reactors doesn't actually solve the problem, as MOX fuel cannot then be further reprocessed and used in thermal reactors again. You still end up with all the fission products, and now the higher actinides from spent MOX, to deal with. Having said that, dry casks are a perfectly cromulent way to deal with spent fuel.

The main motivation to not reprocess fuel was nuclear nonproliferation, because it frees up the plutonium for nuclear weapons. But on the off chance that governments ever want to build a giant pile of nuclear weapons it’s sensible to not get rid of the nuclear waste, since if it ever turns out you do want it again it’s very expensive and time consuming to produce. Since you’ve already gone to all of the effort of min…

I'd say the main motivation to not reprocess is that it costs more than not reprocessing. It's a net economic loss.

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

#543

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…

May I ask your views on Thorium reactors ? Is this the next step/direction in fission reactors ?

Thorium reactors are a type of breeder reactor that can breed using slow neutrons, whereas most breeder reactors built so far use uranium and fast neutrons.

There is a lot of hype about thorium online, but almost all of it is about breeder reactors vs. non-breeders. None of the hype is truly thorium specific.

I wrote up a few pages on it around 2014.

https://whatisnuclear.com/thorium-myths.html

https://whatisnuclear.com/thorium.html

Thorium is often associated with fluid fuel reactors.

https://whatisnuclear.com/msr.html

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

#544

Earlier quoted context omitted.

> 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.

Nuclear in the UK has a capacity factor of around 60%. Availability is in the 70-80% range. Yeah it's (usually) planned, but it's a decently long time in which you need those gas plants. Why not just build solar instead and fuel those same gas plants with hydrogen or methane you plucked from the air with your $20-30/MWh unscheduled electricity? Plus, you can get solar and storage as an off the shelf item today as a r…

Solar requires land area. Storage requires land area. Britain isn't that sunny - particularly not in winter.

Nuclear has a very small footprint on a crowded island.

Plus we have Rolls Royce SMRs who have been building nuclear reactors for a while.

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

#545

Earlier quoted context omitted.

> That rate does not scale negatively with energy prices. It scales positively with population, in the West. I wouldn't uses "prices" here as a framing. If you plot the graphs of worldwide energy usage and worldwide garbage emissions (let's take greenhouse gases or amount of artificialized soil as examples), you will see that they are correlated. We have grown to this gigantic population solely thanks to our mastery…

> If you plot the graphs of worldwide energy usage and worldwide garbage emissions (let's take greenhouse gases or amount of artificialized soil as examples), you will see that they are correlated. You've mentioned this twice, and so it's worth nothing that important factors also correlated in that period of time: the rapid rise of the middle class following the decimation of wealth from the world wars, which led to…

This is super interesting, let's continue the conversation: population increase is a big factor driving energy consumption (and garbage emissions) indeed. Let's assume we have GLOBAL STAGNANT POPULATION GROWTH from today on. So we stay at 7 billion, no problem (this is of course wrong, nicest estimates say we'll stabilise around 9 billion).

The 2 questions now are: 1) what allowed us to reach this amount of population? 2) can this amount of population remain stable with the current inputs given to the system or not?

My two answers:

1) Energy. Abundant energy is what allowed population to reach such heights (x7 in 200 years). In a nutshell it did so by enabling us to get abundant resources, food, medicine and comfort, the first stages of Maslow basically. It did so at scales that would have defied imagination in previous centuries.

2) There are two possible answers here:

- Yes, it is sustainable, meaning we don't deplete earth's resources faster than they renew themselves, situation which will get better with the improvement of technology and will compensate for more and more people getting into the middle class (i.e. more consumers).

- No, it is not sustainable, meaning we are depleting earth's resources faster than they renew themselves, and this situation will get worse with more and more people accessing the middle class (or worse: higher classes) and so the population will collapse at some point due to shortages of food/pandemics/wars etc.

Data to help answer the questions:

- all serious scientific reports (IPCC, https://www.stockholmresilience.org/research/planetary-bound... and others) say that we are currently depleting earth's resources much faster than it can renew them and destabilising many natural systems like climate/life etc to irreversible points

- the average american currently emits 16 tons of CO2/year, the average human emits 4 tons/year, we need to get to under 2 tons/year to make sure the climate does not blow up too much => consequence of this: 5 billion people with a lifestyle a bit closer to the one of americans (i.e. a growing middle class) is much worse than 10 billion with the living standard of people in say, south-east asia or Africa => the living standard is much more important as a factor than the amount of people, if we get more energy with the same amount of people, we'll just keep giving more and more comfort to more and more people, trust me that energy won't stay unused on the side nicely.

- Similar idea to previous point: there is a direct correlation between living standard and amount of destruction of the environment. The rich destroy the planet incredibly more than normal people, even in developped country (symbolised extremely by Brandson & friends). More and more rich/middle class people = more and more energy consumption. This factor is much more powerful than population growth.

- [To be fact checked] I don't remember exactly the numbers but in the past 50 years, optimisations thanks to technology have divided the consumption of machines by 2, while emissions have been multiplied by 4 or 5: so far with what we observe, technology is not a silver bullet to reduce the problem. It is more the cause of the problem by enabling us to do always more and more, with our clumsy, human ways and therefore disrupting nature always more and more.

What are your answers?

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

#546

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…

*These days I don't see why we don't just build lots more regular old LWR fission reactors.* Because they lose money. Nobody, not the USA, Russia, China, France, Japan, Korea has ever made them profitable. They are always subsidized. The CCP bought Westinghouse AP1000s so they could steal their design and they still couldn't make it work. And you can't blame the environmentalists when it's in China. Full disclosure:…

Cost for deeply decarbonized grids are cheapest if you have low carbon firm energy like nuclear. The LCOE numbers thrown around today are meaningless wrt systems costs.

https://www.sciencedirect.com/science/article/pii/S254243511...

nuclear plants save a fraction of their revenue in a trust that pays for decommissioning. for thr vast majority of plants this has been and will be more than sufficient. therr are exceptions but it isnt fair to dwell on them given the other successess.

The dose rates are barely above background already in most of the area around Fukushima. I'm with Elon in that I will gladly eat vegetebles from slightly elevated dose areas because I belive the science that says damger starts at 100 mSv acute/300 mSv annual. Getting an extra 40 mSv in a year is not uninhabitable.

civilian nuclear power has pretty much nothing to do with military nuclear so not sure I follow your point there.

And for the record, here's the full Too Cheap To Meter quote, from a Science Writers Dinner in 1954:

"It is not too much to expect that our children will enjoy in their homes electrical energy too cheap to meter, will know of great periodic regional famines in the world only as matters of history, will travel effortlessly over the seas and under them and through the air with a minimum of danger and at great speeds, and will experience a lifespan far longer than ours, as disease yields and man comes to understand what causes him to age"

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

#547

Earlier quoted context omitted.

building a fission reactor takes one or two decades and its kWh is costlier than alternatives It didn't and doesn't need to be that way. Obviously we need strong regulatory oversight over nuclear power, but a big part of the cost is the need to satisfy incredibly hostile regulations imposed by politicians who are (a) pandering to public fear (b) heavily influence by the fossil fuel industry. Also, talking about kWh c…

> building a fission reactor takes one or two decades > and its kWh is costlier than alternatives > It didn't and doesn't need to be that way. Obviously we need strong regulatory oversight over nuclear power, but a big part of the cost is the need to satisfy incredibly hostile regulations imposed by politicians who are (a) pandering to public fear (b) heavily influence by the fossil fuel industry. That is not true, t…

Fuel diversification is important too. That's something Germany seems to have forgotten when they went all in on natural gas.

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

#548

Earlier quoted context omitted.

I've known about this chart for a long while, but recently I've become skeptical of it. What says that fusion would be a success even if that level of funding was reached? The most mature fusion reactor being built, ITER, is gigantic and it's not clear how it could be made cheaper or miniturized.

Actually it's quite clear: use REBCO superconductors. Tokamak output scales with the square of reactor volume and the fourth power of magnetic field strength. Double the field, 16X the output. Modern REBCO superconductors can support much stronger magnetic fields than ITER will manage. That's why CFS is building a reactor using REBCO which is much smaller than ITER, but should have the same performance. It'll be half…

SPARC's 2025 timeline is a joke. They haven't even started hiring engineers yet, let alone building the thing because they still have no idea how to make a big enough REBCO magnet.

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

#549
post #233

The only true form of green energy other than geothermal. fission, solar, wind, waterfall energy all have their own negative environmental impacts

Geothermal, and all thermal power energy, have a big issue: thermal pollution. You need a lot of water for the cooling phase of the thermodynamic cycle that transform heat into electricity. That's why during drought episodes fission plants have to be stopped. There is however a non-thermal path to fusion energy, aneutronic fusion with direct energy conversion. In this scheme, the fusion reaction produces no neutrons…

Given how much zero carbon warm water we need, it's easy to see zero carbon thermal pollution as a feature rather than a bug.

https://www.oecd-nea.org/ndd/workshops/nucogen/presentations...

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

#550
post #523

Earlier quoted context omitted.

building a fission reactor takes one or two decades and its kWh is costlier than alternatives It didn't and doesn't need to be that way. Obviously we need strong regulatory oversight over nuclear power, but a big part of the cost is the need to satisfy incredibly hostile regulations imposed by politicians who are (a) pandering to public fear (b) heavily influence by the fossil fuel industry. Also, talking about kWh c…

> a big part of the cost is the need to satisfy incredibly hostile regulations imposed by politicians who are (a) pandering to public fear (b) heavily influence by the fossil fuel industry People keep on parroting this, but could you list what these "incredibly hostile regulations" entail? The only "new" thing I know of is the requirement in certain places (like in Sweden) to have ICSS, Independent Core Cooling Syste…

>ICSS isn't that expensive BTW. Vattenfall cited the cost of adding ICSS to their 5 reactors to about 3 billion SEK in 2020. That's about 300 million US dollars with today's exchange rate.

$300m seems pretty expensive to me as a cost to add to what is already the safest energy source in the world by terawatt-hour produced[0]. One-fifth the death rate of rooftop solar. 0.025% as dangerous as oil. Every terawatt-hour of energy a coal power plant produces results in as many deaths as one hundred Fukushima "situations."

[0]: https://www.statista.com/statistics/494425/death-rate-worldw...

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