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Comment by michaelt | Hacker News Reader

AIUI, one concern with nuclear reactors is what to do with the waste.

A 'breeder reactor' is a type of nuclear reactor that makes more efficient use of uranium than 'light water reactors' and with less left-over radioactive waste.

Sounds great, so why do we build anything else? Well, once you've got a breeder reactor it's a very short step to making weapons-grade plutonium. Whereas with light water reactors, this isn't the case.

So the choice of breeder vs light water reactor has pretty big impact on weapon proliferation.

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No, not really. Historically, weapons grade Pu has been produced in dedicated (graphite moderated) thermal reactors, not with fast breeders.

Fast breeders create Pu, yes, but the isotopic composition is poorly suited for weapons.

Actually, Pu from fast breeders is better than the Pu from thermal reactors, since (n,gamma) reactions are less likely on Pu with energetic neutrons.

>one concern with nuclear reactors is what to do with the waste.

Actually, no. The reactor designs in use generate very little waste, just spent fuel rods that have to be kept in safe storage until their radioactivity level goes down to something reasonable. That doesn't take decades, either. The big problem with nuclear waste is the waste from weapons production, and people don't differentiate just like they don't for reactors vs. bombs.

I'm pretty sure I've read articles saying America doesn't currently have a permanent storage facility for nuclear waste such as spent fuel rods, and that the creation of one is politically controversial - have matters changed since I read those articles?

Mostly that for it to matter with any urgency, we'd need to actually be building new reactors. We aren't building them, so we aren't focusing on it and are instead just ignoring the issue. It's not the best decision, but given the problems of today this seems comparatively easy. It just doesn't have much urgency compared to actually building green generation capacity and batteries at scale.

Yet. If we do start building them, they'll probably be small modular reactors instead of the giant old tech ones, and those are both faster and cheaper to build.

They are claimed to be cheaper to build. There is no real world evidence that they will actually be cheaper to build (per unit of power output), and they will likely be more expensive to operate (due to diseconomies of scale in staffing).

Gen III/III+ conventional reactors were also claimed to be cheaper to build. Look how that turned out.

Not really, but bomb waste and spent fuel rods are separate subjects. The volume of fuel rods we're talking about here is small enough that for the most part the spent fuel rods are stored on-site at the plants. Not a great long term solution, especially since the plants don't have facilities designed for it. They're in above ground casks that are lined up in the open spaces around the plant.

However, long term interment isn't what's planned anyway... the fuel rods can be reprocessed into new fuel, and they aren't much of a storage concern anyway... they can actually be stuck on a truck and hauled away in their casks down the highway.

We need somewhere to store the fuel assemblies that's safe and secure (or better than putting them in casks in the open) but we're not looking for a dump site. More like a warehouse facility, where they can sit until reprocessed or dismantled.

Every technology has pros & cons, effects & residues.

Coal : Effect/Pros - Energy/Cheap. Residue/Cons - C02/GlobalWarming

Nuclear : Effect/Pros - Energy/Clean. Residue/Cons - RadioactiveWaste/Contamination.

Where do the nuclear byproducts go currently ? Into the earth? Rivers? Oceans?

30 years ago, we switched from paper based products to plastic, to save trees. Today, we want to switch from plastic based products to paper, to avoid pollution.

Every 'switch' will come with side-effects that the current generation is fine with, because they're not going to be ones dealing with it.

I think it gets dumped off the coast of Somalia, actually.

Obviously, capitalism isn't very good at accounting for externalities, whether they are measured in birth defects, or in degrees centigrade - but I think global warming is a bit more extreme in scale than your typical pollution issue.

>Where do the nuclear byproducts go currently ? Into the earth? Rivers? Oceans?

No where, because there aren't any. If you meant spent fuel if it's not reprocessed it's stored as long as needed to be less dangerously radioactive. If it's reprocessed, any radioactive elements in it that aren't useful are stored and left to decay. Present storage of things like this is on-site as mentioned above, because reprocessing mostly doesn't happen.

The amount of unusable material from reprocessed fuel is tiny, by the way.... even less trouble than storing the spent fuel rods, on the order of a handful of material from a whole fuel rod assembly.

Power generating reactors don't give off anything but electricity, heat, and spent fuel, they are zero emissions.

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