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Xkcd: Greenhouse Effect

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Re: Xkcd: Greenhouse Effect

#271

Post by FrustratedMonky »

smegger001 wrote: post #269
FrustratedMonky wrote: post #259

Earlier quoted context omitted.

Do you have link? I am curious what this design is. If I just randomly search, it is just hundreds of designs, everyone has a 'theory' on some design that is safe and effective. Hard to filter out the 'crack-pot' from the actual physicists. Do you have one in-particular. (edit, also. I ask because Chernobyl was also deemed impossible by 'physics'. Technically it did not melt down first, the reactor didn't 'fail', som…

pebble bed reactors. to quote wikipedia which expalins it better than i can; "When the reactor temperature rises, the atoms in the fuel move rapidly, causing Doppler broadening. The fuel then experiences a wider range of neutron speeds. Uranium-238, which forms the bulk of the uranium, is much more likely to absorb fast or epithermal neutrons at higher temperatures. This reduces the number of neutrons available to ca…

Thank You Yes, guess any built in Negative Feedback would be better than defaulting Positive Feedback.

Guess someone could still do some bad design to cause some other type of rupture that would expel radioactive material, but much less possible.

Re: Xkcd: Greenhouse Effect

#272

Post by trogdor »

hn_throwaway_99 wrote: post #124
dougmwne wrote: post #52

I worked in climate policy for awhile. I got out of it because I lost hope. I believe our governments have lost hope also. Covid taught us that if they inflict the necessary pain to control carbon, our governments will be consumed by populist anger. Only the Chinese system appears to have any hope of controlling people’s behavior that much without riots. And what a terrifying system! Even their control began to slip…

I think your take is giving much too much credit for "governments wanting to do the right thing" if it weren't only for those pesky populists. Take your China example. The issue wasn't just that the government wanted to control Covid and the people pushed back. The issue was that their zero-Covid policy was extremely stupid . I kept thinking "Umm, what do they think is going to happen when they eventually open back u…

>Take your China example. The issue wasn't just that the government wanted to control Covid and the people pushed back. The issue was that their zero-Covid policy was extremely stupid. I kept thinking "Umm, what do they think is going to happen when they eventually open back up - of course Covid is going to ravage through the populace." And that's exactly what happened. The policy did extremely little to actually save lives in the end compared to much less restrictive policies elsewhere.

According to data published by John’s Hopkins, China’s overall number of Covid deaths per 100,000 population was 7.6, compared to 341 in the United States.

Source: https://coronavirus.jhu.edu/data/mortality

Re: Xkcd: Greenhouse Effect

#273

Post by tommiegannert »

walleeee wrote: post #227
tommiegannert wrote: post #221

Earlier quoted context omitted.

> E.g. how do you reach the necessary temps in a blast furnace without melting your heating element? Induction heating? As long as some ferromagnetic material has a higher melting temperature than what you want to melt, this seems solvable.

Thanks, good point. It looks like induction furnaces are already in wide use, though they have some tradeoffs. By the way, I like your writing on your site.

> By the way, I like your writing on your site.

Oh, thank you!

Re: Xkcd: Greenhouse Effect

#274

Post by smegger001 »

FrustratedMonky wrote: post #271
smegger001 wrote: post #269

Earlier quoted context omitted.

pebble bed reactors. to quote wikipedia which expalins it better than i can; "When the reactor temperature rises, the atoms in the fuel move rapidly, causing Doppler broadening. The fuel then experiences a wider range of neutron speeds. Uranium-238, which forms the bulk of the uranium, is much more likely to absorb fast or epithermal neutrons at higher temperatures. This reduces the number of neutrons available to ca…

Thank You Yes, guess any built in Negative Feedback would be better than defaulting Positive Feedback. Guess someone could still do some bad design to cause some other type of rupture that would expel radioactive material, but much less possible.

A rupture is unlikely as most pebble bed designs use helium as the coolent. It being a noble gas it won't react chemically, and unlike water cooled designs it doesn't undergo phase change (liquidgas) so no massive pressure build up. And as there is no oxygen fire is unlikely.

Re: Xkcd: Greenhouse Effect

#275

Post by guepe »

tonyarkles wrote: post #246
guepe wrote: post #245

Earlier quoted context omitted.

That’s interesting. The quotes for the nuclear power plant are really low though. France, which has a lot of knowledge and trained workforce for nuclear, is slowly building a reactor of 1.2gwe for like 20B euros. If you use those numbers… it looks very different. And that’s at least not idealistic price since it’s they are completing the construction.

Yeah, I'm really curious to see how the SMR thing shakes out over time. It does make sense to me that the costs between large bespoke reactors and smaller modular reactors would not necessarily be a linear scaling by MWe. Another factor that affects the price significantly is whether or not the reactor is being built at an existing site that is already licensed or whether it's a scratch-build at a new site. https://e…

Plugging the numbers using France latest EPR: 20B for 1.2GW is 16M per MW Batteries mentioned : 1.7B for 300MW for 16hr is 5.3M per MW for 16hr

So compared to EPR, we could spend another 10M per MW for production…. I saw a relatively conservative price of 2000$/kw AC at https://atb.nrel.gov/electricity/2023/utility-scale_pv

That’s 2M per MW. We can spend 10, an over capacity of 5x ! And that is not accounting for the price of money, it takes very long time to build a nuclear power plant, and you will have your PV plant in the year, probably a couple for mega pack due to demand.

To me, nuclear is not the future.

Re: Xkcd: Greenhouse Effect

#276

Post by tonyarkles »

guepe wrote: post #275
tonyarkles wrote: post #246

Earlier quoted context omitted.

Yeah, I'm really curious to see how the SMR thing shakes out over time. It does make sense to me that the costs between large bespoke reactors and smaller modular reactors would not necessarily be a linear scaling by MWe. Another factor that affects the price significantly is whether or not the reactor is being built at an existing site that is already licensed or whether it's a scratch-build at a new site. https://e…

Plugging the numbers using France latest EPR: 20B for 1.2GW is 16M per MW Batteries mentioned : 1.7B for 300MW for 16hr is 5.3M per MW for 16hr So compared to EPR, we could spend another 10M per MW for production…. I saw a relatively conservative price of 2000$/kw AC at https://atb.nrel.gov/electricity/2023/utility-scale_pv That’s 2M per MW. We can spend 10, an over capacity of 5x ! And that is not accounting for the…

I’m assuming you’re looking at the Flamanville Unit 3? Reading through the history of that build is pretty bad for sure. I’m maybe jaded enough now to expect construction projects to go over budget by maybe 20-30% but lol 580% over budget is not normal at all.

Re: Xkcd: Greenhouse Effect

#277

Post by breakyerself »

charlieyu1 wrote: post #167
breakyerself wrote: post #148

Earlier quoted context omitted.

The planet is warming more than 20X the rate of warming seen through natural processes. There is a unplanned, uncontrolled, planetary scale experiment underway with the chemical and thermal properties of the atmosphere and oceans of the only planet available to us for our survival. The burden of proof is on anyone who wants to continue that experiment to demonstrate that it's safe.

Dinasours were flourishing in an era where atmospheric CO2 was 3x or more compared to current levels

Yes, but the rest of the context of that statement is that earth was a hothouse with no ice, more deserts, and sea levels 550 feet higher than they are now.

Also global warming at natural rates would be less of a concern. This human caused global warming is happening more than 20X faster than natural rates of climate change. Not good if you like your ecosystems intact. Good if your favorite thing about dinosaurs was the mass extinction event.

Re: Xkcd: Greenhouse Effect

#278

Post by CRConrad »

rcbdev wrote: post #3

Mere ~30 years after discovering the Greenhouse Effect we managed to split the atom, harnessing heretofore unimaginable amounts of energy. Yet almost 100 years later, here we are - Oil and gas dependent, boasting an energy and climate crisis, all the while fooling regulators with worthless climate certificates, unaccountable off-shore factories and just plain rampant fraud when it comes to CO2 emissions.

For values of "~30" closer to 50.

Re: Xkcd: Greenhouse Effect

#279

Post by CRConrad »

hnarn wrote: post #121
volemo wrote: post #41

Earlier quoted context omitted.

Sure, there were many a Cleopatra, but only one was the Cleopatra. :D

Much like there wasn't one "Caesar", since it's a title (still kicking in Proto-West Germanic derivatives branching off "kaisar"), but many "normal" people (not history nerds) would still use only the title to refer to Gaius Julius Caesar. Also fun fact -- if you're a history nerd -- "Julius Caesar" is almost equally nonsensical to just "Caesar" since "Julius" is not his name, but refers to his family ("gens"). The f…

> Much like there wasn't one "Caesar", since it's a title

It wasn't (yet) a title during the lifetime of Gaius Julius Caesar, though...

> still kicking in Proto-West Germanic derivatives branching off "kaisar"

Like the non-Germanic Slavic "Tsar".

> Sextus Julius Caesar in around 200 BC, 300 years before Gaius Julius Caesar was born.

Did you accidentally swap the 200 and 300, or are you saying Julius was born ~100 AD?

Re: Xkcd: Greenhouse Effect

#280

Post by brettermeier »

Zealotux wrote: post #81
brettermeier wrote: post #75

Earlier quoted context omitted.

That's good news, take it further!

Yes! As a French, I love breathing polluted air from German coal mines[1]; I will take that over any battle-tested reasonable alternative any day! [1] https://www.euractiv.com/section/air-pollution/news/german-c...

With climate change your reactors will maybe be worth nothing: https://www.reuters.com/business/energy/warming-rivers-threa... That's why france imported much energy from other european countries in that phase, good job.
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