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Nuclear energy is clean

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Re: Nuclear energy is clean

#681

Post by tekknik »

Krasnol wrote: post #673
bilekas wrote: post #660

Earlier quoted context omitted.

Don't take it as a slight. - We're only discussing here > I didn't say this is supposed to be the only way of getting power. Your previous comments do sign you up very much in favour of anything other than nuclear. > . Not just on roofs and you might have heard about wind. That's a thing too. It certainly is, but to my previous point of 'per square meter return' .. Are you planning to organise a turbine with the loca…

> Renewable's are amazing, the more the merrier. But discarding nuclear over it's waste isn't a genuine argument. How isn't it when it actually is in Germany? > We've gotten better than the 60s/70/80 when old plants were built How so when the waste from those reactors is still stored next to those reactors? > That shouldn't stop us from pursuing cheap energy. Nuclear is not cheap. > We also know how to use solar, win…

> Nuclear is not cheap.

It’s getting cheaper. The primary reason it’s not cheap currently is every reactor built is site specific. This will soon change with smaller reactors being built in factories then installed.

> Something you can't say about nuclear. A technology from the past.

This seems like an attack again on nuclear. Stars use nuclear reactions for energy, you’re alive because of a nuclear reaction. Why are you so quick to throw it out?

And you still haven’t answered my question. What do these people do for power? I can’t put a wind turbine on the roof of my apartment anymore than a solar panel. And as your parent stated, there’s transmission and physical surface area concerns.

Once we solve the energy problem, population growth is our next one. We can’t make anymore land, and people advocating for taking large swaths of land, or even ocean, are setting us up for future land use issues. Think beyond the immediate next step.

Re: Nuclear energy is clean

#682

Post by jpgvm »

tekknik wrote: post #613
jpgvm wrote: post #514

Earlier quoted context omitted.

Even if it was a million years it wouldn't matter. The US has the Nevada desert which is effectively a barren wasteland, just shove it in a bunch of containers and leave it there. They already do that for removed nuclear reactors from military vessels (which is actually so it can be seen in satellite imagery to fulfill international treaty requirements.

if we solve the clean energy problem, and energy becomes abundant, then that all becomes very usable land.

And if we don't we all die. Seems like an easy choice to me.

Re: Nuclear energy is clean

#683

Post by ETH_start »

onethought wrote: post #676
ETH_start wrote: post #605

Earlier quoted context omitted.

Not nearly as much as requires to overcome the intermittency issue of renewable power sources.

To completely replace fossil fuel, you need a lot of nuclear plants and nuclear materials and transmission lines. For renewables you can handle a lot of the load near the consumption point and only need to transmit the “night load” which is usually much less.

I recommend you look at the estimates on how much storage and/or transmission lines are needed to go full renewable.

Re: Nuclear energy is clean

#684

Post by credit_guy »

pfdietz wrote: post #680
credit_guy wrote: post #679

Earlier quoted context omitted.

That's the idea behind the gas-cooled fast reactor [1]: The reference reactor design is a helium-cooled system operating with an outlet temperature of 850 °C using a direct Brayton closed-cycle gas turbine for high thermal efficiency. Helium does not absorb neutrons when it passes through the core, and if the nuclear fuel is well insulated (such as the TRISO fuel that Xe-100 plans to use), then you are safe to send i…

A problem with these reactors using TRISO fuel is it greatly increases the volume of waste. The spent fuel is now mixed with a large amount of carbon. Cask storage becomes less practical. Also, any time the temperature is above 550 C you can't use ordinary steels, as they will creep. So these reactors have materials challenges.

All things being equal TRISO fuel should increase the waste volume. But a fast reactor will tremendously reduce both the waste volume (because it can burn U238) and its nastiness (it will have virtually no long half life actinides).

As for steel. Steel is one of the cheapest materials, with an average price below $1000/ton. Nuclear reactors need to use special steels that are resistant to neutron embrittlement, and even those have a price less than $1000/ton. There are more expensive steels out there (for example those used for tools), but generally the price is less than $3000/ton. But let's say that an alloy of steel that resists both neutron embrittlement and temperatures of 750C is $10000/ton. Then a reactor such as Xe-100 which weighs 700 tons in total will be able to procure the steel at less than $7 million, or $28 million for a group of 4; a powerplant with 4 Xe-100 reactors is estimated to cost $2.4 billion, so this cost would be less than 1% of that.

I'm sure there will be 1000 problems that Xe-100 will need to solve before they get their NRC approval and they will be able to economically build their first reactors, but the cost of steel will not be one of them.

Re: Nuclear energy is clean

#685

Post by MisterMower »

throwawaycuriou wrote: post #333
MisterMower wrote: post #229

Earlier quoted context omitted.

And what is the probability of a reactor going down unexpectedly versus a weather event that causes renewable sources to stop producing? I think we learned the answer to that question last winter down in Texas.

Texan politicians didn't miss a chance to blame wind power for the outages. Unfortunately, those initial lies are still circulating. The primary cause was that the pipes supplying natural gas froze. https://www.texastribune.org/2021/02/16/texas-wind-turbines-...

The frozen pipes were a problem specifically because the wind farms weren’t producing.

Replace the wind farms with nuclear power and the problem goes away.

Re: Nuclear energy is clean

#686

Post by pfdietz »

credit_guy wrote: post #684
pfdietz wrote: post #680

Earlier quoted context omitted.

A problem with these reactors using TRISO fuel is it greatly increases the volume of waste. The spent fuel is now mixed with a large amount of carbon. Cask storage becomes less practical. Also, any time the temperature is above 550 C you can't use ordinary steels, as they will creep. So these reactors have materials challenges.

All things being equal TRISO fuel should increase the waste volume. But a fast reactor will tremendously reduce both the waste volume (because it can burn U238) and its nastiness (it will have virtually no long half life actinides). As for steel. Steel is one of the cheapest materials, with an average price below $1000/ton. Nuclear reactors need to use special steels that are resistant to neutron embrittlement, and e…

Does TRISO have higher burnup? Not convinced. Fast reactors that involve reprocessing will greatly increase waste volume due to generation of low level contaminated material in the reprocessing process. Once you let the stuff out of the fuel elements it can get all over things.

Re: Nuclear energy is clean

#687

Post by ncmncm »

ETH_start wrote: post #683
onethought wrote: post #676

Earlier quoted context omitted.

To completely replace fossil fuel, you need a lot of nuclear plants and nuclear materials and transmission lines. For renewables you can handle a lot of the load near the consumption point and only need to transmit the “night load” which is usually much less.

I recommend you look at the estimates on how much storage and/or transmission lines are needed to go full renewable.

People will "estimate" all kinds of things according to their favored assumptions. Most are worth the paper they are printed on.

Re: Nuclear energy is clean

#689

Post by ncmncm »

yellowapple wrote: post #674
ncmncm wrote: post #454

Earlier quoted context omitted.

When your argument depends on promoting falsehoods, one wonders why you bother.

I, too, wonder why people uncritically parrot the fossil fuel industry's anti-nuclear talking points without even having the decency to be paid for it.

Yet, you make shit up on behalf of nukes, under exactly thet arrangement.

Fossil fuels also cost too much.

Re: Nuclear energy is clean

#690

Post by ncmncm »

loup-vaillant wrote: post #636
ncmncm wrote: post #603

Earlier quoted context omitted.

Ask the people who build them. Hydro power systems need to store a year or more. Utilities will need at most a few weeks. You don't need or want a river. Dams are f'ing expensive because they need geological support for extreme pressure. An earthen dike suffices if you don't already have a depression. Only the penstock needs to hold back high pressure.

Give me sources or it does not exist. I'm aware of dams. I'm not aware of your fancy alternatives. It is therefore reasonable to assume that those fancy alternatives aren't widely deployed. And that the main reason for this is that they're more expensive (per energy unit). Without sources, your (admittedly plausible) qualitative arguments are just a pretty story.

You are welcome to read up, yourself.

California has constructed dozens of high-altitude, low-head earthen dams on the same principle, over the past century, with penstocks down to lower-altitude turbines, and has lately converted many of them for pumped hydro.

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