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Ultra Safe Nuclear

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Re: Ultra Safe Nuclear

#81

Post by evgen »

adrianN wrote: post #61
mdorazio wrote: post #50

Earlier quoted context omitted.

Not really. It's rather expensive (billions of dollars) to setup a nuclear plant in the first place, even before a single fuel rod shows up. Meanwhile solar is so cheap and easy that you can install panels on your roof yourself.

I agree that traditional nuclear makes little economic sense. But I disagree that this is inherent to nuclear power, because there might be a different reactor design that doesn't cost billions of dollars to set up. We just haven't found it yet.

One of the specific targets of the modular reactors that are now getting approval are these cost issues. If you build one reactor a year it will be big, bespoke, and incredibly overpriced. If you build a hundred modular reactors every year the cost will drop significantly.

Re: Ultra Safe Nuclear

#82

Post by adrianN »

dangerface wrote: post #67
detritus wrote: post #44

Earlier quoted context omitted.

> The fact that ALL energy in our solar system comes from the sun is irrelevant Except human-made nuclear fission energy on Earth, somewhat ironically, given the thread.

The fuel burned in those reactors comes from the sun and the reactor releases it.

The fuel in fact doesn't come from the Sun, but from other stars that went super nova before the solar system was formed. Normal fusion in stars in not hot enough to produce such heavy elements.

Re: Ultra Safe Nuclear

#83

Post by detritus »

dangerface wrote: post #67
detritus wrote: post #44

Earlier quoted context omitted.

> The fact that ALL energy in our solar system comes from the sun is irrelevant Except human-made nuclear fission energy on Earth, somewhat ironically, given the thread.

The fuel burned in those reactors comes from the sun and the reactor releases it.

I'd love to know more about how heavy elements got from the sun into the interior of our planet and then back out to near the surface again. Where can I learn about this process?

Re: Ultra Safe Nuclear

#84

Post by VBprogrammer »

karpierz wrote: post #59
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…

How would you turn off the outside source, and how would the mechanism differ from existing safety features?

The Wikipedia page is a lot more detailed than I could hope to be, presumably you just turn off the power to the particle accelerator.

Existing safety measures rely on some degree of integrity in the reactor at the time they are triggered. If it gets too damaged before the control rods are inserted it may not be possible to insert them.

https://en.m.wikipedia.org/wiki/Subcritical_reactor#:~:text=....

Re: Ultra Safe Nuclear

#86

Post by carry_bit »

merb wrote: post #31
manfredo wrote: post #17

Earlier quoted context omitted.

Because it's not a problem. There's actually very little of it. It occupies a volume the footprint of a football field and 10 yards high [1]. Storing it is pretty foolproof: bury it in an area with no aquifer. The main risk of contamination is getting into the groundwater. If there's no groundwater the risk of contamination is eliminated even if the containers decay over time. And lastly, it doesn't make sense to bur…

1. How long does it need to be kept safe? 2. How to find a storage facility that can keep it safe that long? 3. How to ensure that a facility does not contamine other stuff in X years? 4. if it is recycable why does nobody do it? 5. if it is so easy to store it safe, why does not country have a TRUE final depot? yeah coal is bad, but why compare it to coal in the first place when we want to reduce such things anyway?…

https://whatisnuclear.com/waste.html covers many of your questions.

With full processing, it only takes 500 years before the radioactivity drops to that of natural uranium ore.

Re: Ultra Safe Nuclear

#87

Post by semi-extrinsic »

gruez wrote: post #27
nimish wrote: post #18

Safety is no longer the reason Nuclear is not worth it. The sun is a giant, free nuclear fusion plant in the sky. We can capture 1/5th of its output per square meter. For free! The wind -- caused by solar heating -- also generates free power. The cost of harvesting it is now so low, and will always continue to decline as any technology will, that any fuel-based generation mechanism is going to be rendered uneconomic…

>We can capture 1/5th of its output per square meter. For free! except you know, the solar panels. by the same logic you can you can capture fission power for free, all you need is set up the reactor.

There was a comment here about cleanup costs of nuclear vs. solar, that was deleted while I was typing my response to that. I'm just gonna copy in my response here, because I think it's an interesting topic:

Are we really sure solar panels are much easier to dismantle on a euro-per-kWh basis though? That is, if you divide the total cost of dismantling and recycling a solar power plant, divided by the total amount of energy produced over the lifetime, does solar power do much better than nuclear?

Nuclear power in Germany (17 powerplants) has produced well over 5 million gigawatthours over the lifetime so far. It's hard to put good numbers on the cleanup costs, but somewhere in the ballpark of 50 billion euros is probably correct. (Keep in mind that some cost is the government paying the powerplant owners compensation because they are forcing them to shut down long before end-of-life).

So that gives you around 0.01 euros per kWh. A solar panel with 20% efficiency placed close to the equator produces 500 kWh/m2/yr. Over 30 years of lifetime that would produce 15 000 kWh/m2.

Are you sure you would spend significantly less than 150 euros per square meter of panel to dismantle, transport and recycle the solar panels?

Re: Ultra Safe Nuclear

#88

Post by dangerface »

slezyr wrote: post #80
nimish wrote: post #18

Safety is no longer the reason Nuclear is not worth it. The sun is a giant, free nuclear fusion plant in the sky. We can capture 1/5th of its output per square meter. For free! The wind -- caused by solar heating -- also generates free power. The cost of harvesting it is now so low, and will always continue to decline as any technology will, that any fuel-based generation mechanism is going to be rendered uneconomic…

> The sun is a giant, free nuclear fusion plant in the sky. We can capture 1/5th of its output per square meter. For free! Are going to clean solar panels/mirrors for free? > Bahawalpur is desert terrain , having high dust count, therefore, the efficiency of panels were reduced by 40%. It required 30 people to clean panels with 15 days to restore the panels back to their full capacity, which reduced production of ins…

Do you get out of your car to wipe your windscreen when its raining? This cleaning problem seems like something that would be super easy to automate, I dunno why they would higher 30 people to do this when you could higher one engineer.

Re: Ultra Safe Nuclear

#90

Post by shpeedy »

manfredo wrote: post #10
xibalba wrote: post #3

Assuming nuclear truly can be ultra safe, how do you convince a public that has seen Chernobyl, Three Mile Island, and Fukushima to get on board? Particularly when the "competition" (solar, wind, etc) has such a strong tailwind.

First, point out that Chernobyl, 3 Mile Island, and Fukushima amount to extremely small numbers of deaths relative to the power these plants generated. For three mile island and Fukushima this figure is zero among the public. Less than two dozen among the plant workers (all of which died due to the hydrogen explosion not radiation). The areas that were evacuated are now safe to return. Chernobyl was worse, but th Sov…

You are joking about "small numbers of deaths", right?, because this millennia is not over yet.
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