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Ultra Safe Nuclear

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Re: Ultra Safe Nuclear

#461

Post by fulafel »

JanSt wrote: post #407
fulafel wrote: post #382

Earlier quoted context omitted.

Nuclear has had 70+ years and untold zillions in government research money and subsidies poured into it[1] - if the same level of investment over time had gone into renewables, imagine where they'd be now. [1] worldwide - germany, uk, canada, france, russia etc in addition to the us - everyone did build their experimental gas/molten salt/fuel recycling/pebble bed etc reactor research programs and reactors. not to men…

Germany alone spends ~$1.2 trn (that would be ~4.8trn on a population adjusted basis for the USA) on the Energiewende, and Germany is far away from being 100% renewables. The EU now plans to invest another trillion € till 2030. A lot of money is poured into renewables.

Yep, there is a lot being done today of course and progress has picked up in recent years. But knowing what we know, it's still underfunded.

Re: Ultra Safe Nuclear

#462

Post by pfdietz »

f154hfds wrote: post #459
pfdietz wrote: post #349

Earlier quoted context omitted.

The distributed nature of renewables is actually a huge advantage. It means the renewable system is extremely fault tolerant. Not only does that help in operation, but it means installation is much more forgiving of low quality work (so you can use cheap labor that's easy to train). Screw up 1% of the modules in a PV field and output is down 1%. Screw up 1% of the welds in a nuclear power plant and you have a world o…

This is a very weak argument for renewables. You have to make the case that nuclear is fundamentally not able to work in a similar way. The very article we're commenting on is demonstrating the more 'distributed' nature a new generation of nuclear power plants can offer. Your other argument about cheap labor is completely ignoring principle 3. above. Saying cheap labor for an industry is _inherently_ good is basicall…

It's not a weak argument at all. The units in renewables are small (for PV, very very small), compared to the units in SMRs. What's more, the consequences of failure of the units in renewables are minor, compared to the consequences in a reactor.

It has not been demonstrated that the diseconomy of scale in SMRs is actually tolerable. The experience at NuScale is not providing much comfort there.

Of course the lower demand for skilled labor is good. "Civilization advances by increasing the number of things that can be done without thinking about them." The simpler the task, the less training is required, and the faster workers can be brought up to speed. The high skills needed for nuclear work are one of the reasons nuclear builds are in trouble.

(You might object to that if you are a skilled laborer feeding off this trough. Well, too bad, the purpose of energy isn't to employ you. You are a cost, not a goal.)

Nuclear has taken on an religious fervor that's not based anywhere in reality. Nuclear is demonstrably a failure, yet the proponents are blinded by their dogma.

Re: Ultra Safe Nuclear

#463

Post by belorn »

belorn wrote: post #421
ajross wrote: post #237

Earlier quoted context omitted.

And unlike a natural gas plant, it costs 3-10x what the equivalent generating capacity in renewables would cost. I come to post this Same Thing every time this discussion comes up. It's not about safety. Everyone serious understand nuclear, even current technologies, is "safe enough" to be useful to build out. Nuclear is outrageously expensive , though. And new reactor designs don't seem to be making much progress on…

The growth numbers currently show that for every extra watt of renewable energy consumed globally, 10 more watts of fossil fuels get consumed. ( https://ourworldindata.org/energy#energy-consumption-by-sour... ) Looking at the multiple data sources at https://en.wikipedia.org/wiki/Cost_of_electricity_by_source , there is several patterns that should be fairly clear. Gas and oil is very cheap to build, and the market p…

The downvotes demonstrate quite clearly what earnest environmentalist think about continuing the existing trend of fossil fueled energy.

Re: Ultra Safe Nuclear

#464

Post by whatshisface »

zaroth wrote: post #138
whatshisface wrote: post #125

Earlier quoted context omitted.

Using present-day numbers to say that solar deforestation will not be a problem is just as fallacious as using today's temperature to say that global warming is not a problem.

That is a flawed comparison, and a poor argument. Present day worldwide energy usage is a real metric which allows us to calculate the present day 200,000 sq mile figure. Today's temperature doesn't allow calculating anything relevant to global warming. I assumed you were being hyperbolic and thought some readers might be curious about the hypothetical area of panels required to meet the entire world's energy demand.…

Existing deforestation is already done to collect solar energy, to power crop growth.

>Today's temperature doesn't allow calculating anything relevant to global warming.

Yes it does, it allows us to calculate the extent to which global warming has progressed... to date. Just like the current global energy usage lets us calculate the progress of energy use growth, to date.

Re: Ultra Safe Nuclear

#465

Post by sparkie »

pfdietz wrote: post #441
sparkie wrote: post #373

Earlier quoted context omitted.

But this is missing the elephant in the living room (this thread), which is nuclear. One of the main issues with nuclear is that it isn't cost effective to turn on/off to meet demand changes in day and night. Nuclear power stations usually only generate energy for the baseload. If we were to cut energy consumption down at night (by increasing costs), the baseload would also drop, and leave an even larger gap to meet…

No, it's not missing nuclear. Hydrogen is the stake through the heart that kills the last argument for nuclear (that batteries can't handle long term load leveling). With reasonable projections of where the costs of renewables and storage are going, nuclear gets optimized right out of the picture.

Yeah, I can't take you seriously. GL with your blackouts and energy quotas, oh, and reliance of fossil fuels. Where do you think the energy is going to come from to perform electrolysis for hydrogen? solar? You are nowhere near meeting basic needs yet with solar, wind, tidal, geothermal combined. (3 out of the 4 can be intermittent/dependant on environmental conditions and are not reliable). Remember, energy demand is going to continue increasing. By the time your renewable utopia exists, you're going to need to double or triple its capacity.

Perhaps I'm unaware of some technological breakthrough which can produce hydrogen using little energy?

Nuclear is great once up-front costs are paid. Most future energy demand will be met by nuclear. Cleaner renewables will be there to provide additional capacity above baseload, but I wouldn't depend on them to meet basic needs.

I have pondered whether it would be possible to generate hydrogen more cheaply via concentrating solar or geothermal. The hotter you can get water before performing electrolysis, the less electricity will be required. Above 3k Celsius, the atoms in water will dissociate without electricity. You might have a reasonable argument against nuclear if you don't need to spend 3x the electricity creating the hydrogen than you'll get back from it.

Re: Ultra Safe Nuclear

#466

Post by VBprogrammer »

Symmetry wrote: post #171
VBprogrammer wrote: post #4

I once wondered if it would be possible to have a nuclear power station which operated subcritically with extra neutrons injected from an outside source. The advantage I saw was that turning off the outside source would instantly stop the reaction, no worrying about articulating fuel rods and poison injectors. Unfortunately decay heat is still an issue. Turns out it's potentially a thing but has some technical challe…

The problem is less about preventing criticality and more about handling the decay heat from all the isotopes produced when it was critical. That's going to give you 10% of the heat you had been producing with the reactor on for a little while after you stop the chain reaction.

Yes, that has been the common factor in most incidents. Chernobyl being the exception, they didn't manage even manage to get the control rods fully inserted before the shit hit the fan (poor reactor and control rod design).

Still, the British AGCRs were recently fitted with articulating control rods because if the reactor core was damaged they might not be able to insert them normally.

Re: Ultra Safe Nuclear

#467

Post by matheusmoreira »

pfdietz wrote: post #343
matheusmoreira wrote: post #167

Earlier quoted context omitted.

A problem inherent in renewables is they depend on climate. Doesn't make for reliable or predictable power output. Climatic conditions could suddenly change and wipe out part of your energy capacity. Happened in my country and we ended up with expensive, rationed power: https://en.wikipedia.org/wiki/Electricity_sector_in_Brazil#T... It's useful to have an alternative that allows burning fuel in order to generate ener…

If we plug in Brazil (2011 weather data, 2030 cost model) into https://model.energy/ you get very good prices in a 100% renewable system. Mostly solar, with hydrogen backup (although this doesn't take into account Brazil's hydro resources which could make things even cheaper.)

Hydrogen for energy generation? I've never seen that. Does it provide on-demand power generation like fossil fuels? If so then that's pretty awesome, I bet it's even better than stuff like coal. Not really educated about it though.

Also I'm not talking about energy prices. I'm talking about the reliability and predictability of the overall system. Hydroelectric power here in Brazil is constantly threatened by lack of rain. Solar power is threatened by long periods of cloudy weather. Every time it happens it shows up all over the news. I remember it happening a fes years ago.

I'm not saying these energy sources are not good. They're awesome. The problem is they depend on climate so we can't always count on them. Gotta have the ability to burn some kind of fuel to compensate. If hydrogen works as a renewable fuel then it'd be great!

Re: Ultra Safe Nuclear

#468

Post by specialist »

godelski wrote: post #286
ajross wrote: post #237

Earlier quoted context omitted.

And unlike a natural gas plant, it costs 3-10x what the equivalent generating capacity in renewables would cost. I come to post this Same Thing every time this discussion comes up. It's not about safety. Everyone serious understand nuclear, even current technologies, is "safe enough" to be useful to build out. Nuclear is outrageously expensive , though. And new reactor designs don't seem to be making much progress on…

> But as a numerate and earnest environmentalist, I don't see where the case for it lies. There's two main benefits to nuclear: 1) The big case is the lack of good power storage. While areas like the South West US have plenty of sunshine to go around, most other places don't have this luxury. Therefore you need substantially more storage. I'll give you an example, I've been sitting in Oregon for the past week and sun…

Independent of energy production, I support any nuclear program that reduces our stockpiles, on any time scale. Bonus yay if we also manage to get some economic benefit.

Re: Ultra Safe Nuclear

#469

Post by DennisP »

sbierwagen wrote: post #400
nine_k wrote: post #241

Earlier quoted context omitted.

Two questions: (1) Night time. (2) Quiet time. Of course there are batteries! But factoring them in seems to increase the cost significantly. Power lines and cross-continent smart grids are fine, too — but also not free to build and operate. So a self-contained unit that does not depend on weather, does not need refueling, and includes its own energy accumulator has some appeal.

>Night time Why does electricity at night need to cost the same as electricity during the day? Would Western civilization collapse if it cost twice as much? Three times as much? How much trouble do we need to go to so aluminum smelters can run at 100% capacity at 2 AM?

If you're going to shut down factories at night, that itself is a cost that should be accounted for. If you're shutting down for eight hours a day, you increase capital costs by a third.

That's worth paying if it's the only option to address climate change, but if the main argument against nuclear is cost, it's not a fair comparison if renewables externalize cost to the customers.

(Also, aluminum smelters in particular take damage if they shut down more than five hours or so.)

Re: Ultra Safe Nuclear

#470

Post by tlb »

marcosdumay wrote: post #456
ChuckMcM wrote: post #357

Earlier quoted context omitted.

That isn't my understanding, would love to learn more about how you come to that conclusion. (Ideally based on an idea like the one in the article vs just your run of the mill designed in 1950 power plant :-))

Are they changing any relevant part of the power generator compared to a 1950 plant? Are they at a minimum heating the steam into a higher temperature than what a modern coal plant do? (Are they using water? Because coal works on the limits of what you can do with water already.) This article seems to have no detail at all, but all the information there seems to be about the reactor. Guess what, you won't build a nuc…

Most nuclear plants operate at lower steam temperatures than coal, because thermal efficiency isn't so critical and lower temperatures are less wear on the pipes and turbines.

WRT cost: Nuclear plants could be cheaper. Because, for instance, coal plants require scrubbers to meet particulate emissions rules, which are very expensive to install and operate. And coal is expensive: mining, transporation, cleaning.

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