Comment by dmos62 | Hacker News Reader

Comment by dmos62 | Hacker News Reader

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> unsolved problem of disposing the nuclear waste

I'm not sure what you mean by unsolved disposal. Nuclear waste from power plants is stored in secure facilities. It takes up a manageable amount of space, is low maintanance and isn't dangerous. Furthermore, future reactors will be able to reuse it; the current reactors only use up a small fraction of the fuel. So actually, you wouldn't even want to throw it away.

Also, nuclear fuel is advantageous logistically. A typical plant needs 1 train-load of fuel a year. That's a relatively small freight, you can ship that from anywhere around the world. On the other hand, for carbon-fuel powerplants, you need a train load of fuel per day.

I'd love to see the planet off non-renewable-fuels, but a big hurdle is that, unless we figure out storage, the renewable energy sources have to be supplemented with something for when it's night and there's no wind. I don't see a better option for that something than nuclear. Of course, an alternative would be for society to switch to an energy usage scheme that doesn't presume that power is uninterruptable. However, that would require profound changes to our everyday lives, and I don't think we're quite mature enough as a species to go through with something like that at scale.

The spent fuel building on most all sites have a corrugated metal roll up door. It is, without a doubt, the most vulnerable area in the plant. Spent over 20 years as an Operations Plant Supervisor, licensed at CE PWR plants.

What do you mean by "secure facilities"? Yes, currently the nuclear waste is in intermediate storage facilities. Which are buildings, with an useful life time of 50 years. Unless a nuclear technology for reusing or processing the waste appears, we are talking about safe storage for thousands of years.

I don't think nuclear waste is as big a problem as you might think it is: https://what-if.xkcd.com/29/

And on a side note, are solar and aeolic scalable enough to support (let's say) the entire US ?

How much of the country would physically need to be covered for that? Cause I've seen claims that it's just impossible

Nuclear waste won't kill anyone, as long as it is contained in the storage containers. We just don't have found a way to keep it guaranteed safe for centuries.

Solar alone could easily power the country. Covering large parts of Arizona would produce enough energy to power the whole world. Powering the US, especially distributing it across the states, makes that an easy job. And of course, there is wind. Probably it would be enough to cover all rooftops to power any state.

On Sunny days, Germany can power 30% of the grid by solar only, and that is in a country which is less suitable for solar than any place in the US except Oregon.

regarding the xkcd, it's not really accurate (it seems to consider only the neutrons as "radiation"), for a somewhat better description see the first answer at

https://physics.stackexchange.com/questions/187605/does-wate...

The cartoon only argues that the material is safe to swim next to in a pool. It doesn't argue that storing spent fuel in a pool for hundreds of years is a good idea because of it (it isn't).

Highly active waste is stored to be separated from the biosphere 10k to 100k years (If stored in a pool that's 200 to 2000 pools assuming a 50 year lifespan and hoping there are no massive earthquakes to ruin that plan - and hoping people are still around to rebuild the pools).

The alternatives for storing includes the pool idea (however difficult), as well as storing in several km deep drill holes (downside not being able to move it again). The most realistic one is storing it in earthquake-safe bedrock at 500m depth, in large metal capsules embedded in clay or salt. Needless to say, even for a small amount of material, this is a rather expensive storage.

There’s lots of other hazardous waste which remains dangerous literally forever. Only needing safe storage for thousands of years is pretty good.

Future reactors? Rosatom has 800 MW breeders now!

It has one 800 MW breeder that has been operating at full power for two years. Plans to build more of them in China appear to have been shelved. The successor BN-1200 implementation has also been suspended. The 6 reactors that Russia currently has under construction are all PWRs. I think that referring to breeders as future reactors (in the context of commercial power plants) is appropriate.

But it’s not like it’s a brand new design just out of prototyping. It’s a continuation of a 350 MW unit that ran for decades and provided drinking water.

Point is the Russians have breeder technology fairly well figured out.

The BN-800 is certainly better proven than other breeder designs, which are either much smaller or operate only in PowerPoint slides. Can it or something like it be built at prices to make breeder power reactors commercially mainstream? That's still unknown. Commercial viability is the biggest unknown for every new power reactor design.

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