Nuclear waste from small modular reactors

[caraher]

Another factor to consider

Small modular reactors (SMRs), proposed as the future of nuclear energy, have purported cost and safety advantages over existing gigawatt-scale light water reactors (LWRs). However, few studies have assessed the implications of SMRs for the back end of the nuclear fuel cycle. The low-, intermediate-, and high-level waste stream characterization presented here reveals that SMRs will produce more voluminous and chemically/physically reactive waste than LWRs, which will impact options for the management and disposal of this waste. Although the analysis focuses on only three of dozens of proposed SMR designs, the intrinsically higher neutron leakage associated with SMRs suggests that most designs are inferior to LWRs with respect to the generation, management, and final disposal of key radionuclides in nuclear waste.

[CentralMass]

1. I have no expertise here but my understanding is that the molten salt reactors

are much less prone to nuclear meltdown if not "immune" to them. Given the extreme radioactive release and environmental contamination caused by a nuclear meltdown, Chernobyl amd Fukushima come to mind, is pursuing that technology with a storage solution the better option ?

[caraher]

2. This study does look at one molten salt SMR design

The focus here isn't on reactor safety so much as a narrower question of the effect of reactor scale (specifically small modular reactors vs. a more "traditional" GW-scale power plant) on radioactive waste production. This narrower question may not be the most important one, of course, and one can make a good case that the waste problem isn't as important as the resilience of given reactor design against certain failure modes.

I thought it was interesting that you may wind up with a very different waste problem to solve with 10 100-MW SMRs vs. a single GW reactor.

[CentralMass]

3. Thank you for the article. I only had time for a quick glance but will give it more time later.

[NNadir]

5. The paper has been criticized, but probably on the wrong grounds.

A small modular reactor has very high burn up, meaning that it fissions actinides to produce fission products.

The big deal with so called "nuclear waste" is that the actinides are long lived.

If one is familiar with the chemistry of fission products, and for that matter with that of actinides, this is not a problem.

If on the other hand, one defines the fission products as "waste," one may have a problem, if and only if one can show an example of so called "waste" actually injuring someone.

One would need to compare it to the 18,000 to 19,000 people who will die today, who died in the same numbers yesterday, and the people who will die in the same numbers as will die tomorrow from normal air pollution, never mind the people dying today, yesterday, and tomorrow from extreme heat.

High fuel burnup is like high efficiency on a car.

As it happens, fission products are remarkable tools if one lets go of fear and ignorance.

If one is unwilling to let go of fear and ignorance, one accepts six to seven million deaths per year, perhaps more because one has selective attention.

I happen to know of a use for pretty much every fission product, and in fact, every actinide. I'm paying attention to what matters. Fission products can do what no other materials can do as well. For example, as I recently noted: Nice Mechanistic Graphic on the Mechanism of Mineralization of PFAS by Irradiation.

From my perspective, anyone worried about so called "nuclear waste" in the face of what is happening with dangerous fossil fuel waste must be out of his or her mind.

[caraher]

6. Leaving aside the pejorative "waste..."

... it does seem wise to take a full-life-cycle perspective on any large-scale processes, whether one regards the non-energy products of a reactor as a waste problem to be solved or as materials whose particular characteristics can be put to good use. The fact that those may differ in important ways for SMRs (if correct) seems important from either perspective.

[NNadir]

8. Any "full cycle" analysis would need to take a look at the obvious consequences of fossil fuel waste

The conversation borders on insane in that context.

[caraher]

9. I don't think that's the relevant discussion

If you're going to build out nuclear, do you invest in large power plants or SMRs? That's the kind of question this paper might help address.

I did not post this as a "oh noes, SMRs make nuclear waste so let's keep burning fossil fuels" piece. Anyone viewing it through that lens is indeed asking the wrong questions.

[NNadir]

10. I disagree. The term "nuclear waste" is deliberately a selective attention phrase.

We do not call air pollution "fossil fuel" waste, although it is, nor do we call climate change "fossil fuel waste" although it is.

The term "nuclear waste" is a loaded term although if you press anyone using it, they are at a loss of showing that it kills people on any kind of meaningful scale.

I contend that any conversation that focuses on any kind of energy related waste - including the waste of energy forms I oppose, such as solar and wind waste - is disingenuous unless it is comparative.

Why does nuclear energy need to be without risk when other systems are vastly more risky?

As it happens, I know a vast amount about used nuclear fuels, and I find these evocations to be deadly, since pretending that only so called "nuclear waste" needs discussion focuses attention precisely on what that doesn't matter. It is deadly since it prevents us from saving lives that are lost to climate change and air pollution, which kill people.

They are the precise and exact equivalent of Hunter Biden's laptop compared to billion dollar pay offs to Jared Kushner.

[hunter]

4. Are these waste streams any worse than fossil fuels?

[caraher]

7. Certainly beyond the scope of the paper

I think this is more about the question, if you want to use nuclear energy, are SMRs the way to go vs. the more conventional nuclear power plants. It's just one more factor to consider if you're making that kind of decision.

I don't think it fundamentally affects the broader questions regarding nuclear energy in lieu of fossil fuels.