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Small nuclear reactors: tiny NuScale reactor gets safety approval

popularmechanics.com

191–200 of 554 posts

Re: Small nuclear reactors: tiny NuScale reactor gets safety approval

#191

Earlier quoted context omitted.

Wasn't the big push (or maybe big PR push) for more research and development of Thorium reactors a few years ago because they fail closed/safely? That seems like the kind of thing you'd want for smaller reactors (which I assume means more and more geographically diverse, but don't really know).

There's no research being done on materials to safely contain molten radioactive salt, that research could be dangerous, pretty much only superpowers would have the resources to do the research.

This was being done three years ago: https://www.powermag.com/thorium-molten-salt-reactor-experim...

Also, I believe Copenhagen Atomics is doing this at the moment, but couldn't (quickly) find a reference.

Re: Small nuclear reactors: tiny NuScale reactor gets safety approval

#192

I was thinking Nuclear would be the stable baseline for renewable. But this is not a sustainable option. We need to enforce hydrogen. Do not submit to the fallacy of nuclear waste disposal. First Elon needs to fix space travel and make transport into the sun feasible. And we will have iter by then.

Hydrogen can be a practical fuel, but you need energy to extract it, which could very well be nuclear

Or solar. Or wind. Or tidal. The beauty of hydrogen is its a great way of time-shifting intermittent energy on a large scale (assuming a large enough water supply) for later use. I’m talking primarily about electricity generation as opposed to fuel for vehicles.

Re: Small nuclear reactors: tiny NuScale reactor gets safety approval

#193

Earlier quoted context omitted.

You don't need to be an expert. Ask anyone who has owned an in-ground pool. Leaks are rare but do happen.

Nuclear power plants were designed with this in mind. It would take a substantially larger earthquake to damage a nuclear power plant and cause it to leak than a commercial pool. Such a comparison is in bad faith and disingenuous.

It's a people problem.

People are fallible on the best days, assuming everyone did their very best from nuclear physicists to construction workers, mistakes are made. You take steps to reduce the risk. Research gets review. Engineering schematics get review. Construction gets inspection. Still some mistakes will get through.

And people always act their very best all the time right?

You can even have a perfect design, perfect construction, that is mismanaged years after it's built, after the original engineers and bureaucrats lose control.

The same people problems apply to basically every human endeavor, but nuclear's capability to cause accidents that have a lasting impact is pretty scary. You don't feel even a twinge of existential dread when you think about? If you don't, then I don't think I want you working on a reactor.

Re: Small nuclear reactors: tiny NuScale reactor gets safety approval

#194
post #171

Earlier quoted context omitted.

Sigh... If only a method for converting carbon dioxide emissions into another gas actually existed in nature.

Plant trees and burn coal? That’s your plan?

Every time I read something like this, my hubris alarm goes off. We couldn't even get trans-fats right, so I don't see how we're going to cover all the contingencies for something like this.

Re: Small nuclear reactors: tiny NuScale reactor gets safety approval

#195
post #12

This is huge. Not only are micro reactors far more economical, it dramatically reduces the need to maintain a massive nationwide grid and provides flexibility to people in remote areas including greater autonomy. Efficiency should be greater without massive transmission line losses. Might start fewer fires in California too.

> This is huge. Not only are micro reactors far more economical

No, they aren't. They are more expensive per unit of power produced, by far bigger than any other powerplant in practical use.

The only way I see nuclear getting economical is it getting bigger. Nuclear's biggest advantage after the cost of fuel is its huuuuuuge power density, and power scalability. With currently technology level, it's possible to generate multiple gigawatts from a single reactor.

> it dramatically reduces the need to maintain a massive nationwide grid

It would not. Grid maintenance are quite non-linear, and high voltage lines are actually much cheaper per unit of electricity transferred than residential links.

Very high voltage DC transfer is very economical, efficient enough for intercontinental connections, but very expensive.

Re: Small nuclear reactors: tiny NuScale reactor gets safety approval

#196

I think it's disingenuous to argue the economics of nuclear without mentioning: "DOE reported that it faced an estimated $494 billion in future environmental cleanup costs — a liability that roughly tripled during the previous 20 years." https://www.gao.gov/assets/700/696956.pdf

My understanding is that these DoE sites are weapon sites, such as Hanford. These are a different ball game than power plants. They use different technologies and have different kinds of waste. Sure apples and oranges are both round fruits, but aren't one to one comparisons. List of sites https://www.dnfsb.gov/doe-sites

Isn't more of Apples to Macintoshes to Honey Crisp to Granny Smith? It's all nuclear waste, but just a different variety.

Re: Small nuclear reactors: tiny NuScale reactor gets safety approval

#197
> The current design, which still has several steps until it can be constructed in the wild, is for 50 megawatts per module. NuScale seeks to apply for a 60-megawatt version next.

I'm very impressed by that output. It will make a difference with areas of high solar and wind generation, which can't maintain a sustained high duty cycle.

I expect these types of reactors to be in places to augment solar and wind, not replace it.

Re: Small nuclear reactors: tiny NuScale reactor gets safety approval

#198

Thinking about the cooling pool: Could you just make an off-shore in-ocean "farm" of these?

Salt water might add to your corrosion issues. Also, physical security of nuclear reactors is a big deal. Now you need a navy to do it.

Re: Small nuclear reactors: tiny NuScale reactor gets safety approval

#200
post #166

Earlier quoted context omitted.

The world is filled with naturally occurring phenomena far more dangerous than a big pile of low-grade nuclear waste. The really dangerous stuff ceases to exist after a few decades of sitting in a cooling pond, and then what’s left has such a long half life that it’s not particularly threatening. Water is an incredible radiation dampener, and the ocean is already chock full of dissolved uranium. The only reason we do…

You're underplaying the danger and overplaying the value. Who exactly is investing in this "green gold"? If it's so valuable why does no one actually want it, and why is the DoE stuck with half a trillion liability?

Isn't the "green gold" as you state it what the traveling wave reactor folks https://www.terrapower.com/our-work/traveling-wave-reactor-t... hoping to use to generate their power?
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