In terms of deaths per kWh generated, nuclear is already the safest form of energy generation we have.
Where nuclear fails, and where improvement is desperately needed, is ability to deliver on budget and within schedule.
What is NOT needed is minor incremental safety improvements at significant cost (e.g. ATF's that the article discusses).
Now, more substantial improvements, e.g. non-LWR designs, passive walk-away safety, modular design, etc., I'm all for those.
We need ways to minimize financing costs during construction, and get the number of staff required at operating plants way down to decrease O&M. My favorite solution? Shipyard-constructed nukes on floating platforms, tugged to locations for power and tugged back to port for maintenance. Solves almost all problems assuming you can get them to operate largely autonomously. In attacks or ship collisions, design it to sink safely and cool itself with seawater. Build in a recovery operation to the design.
Also, the nuclear industry really needs to find ways to consolidate effort. There are literally 50+ SMR designs in work right now, and dozens more larger reactors. The industry is wayyy to small to be fighting over limited investor and government money to develop that many reactors in isolation.
What’s your opinion on Thorcon?
Also I’m wondering if you have some thoughts on this: I’ve been wondering what holds us back from taking a scale out approach rather than a scale up approach we have now (e.g. with EPR design now producing 1.6GW). Instead couldn’t we pump out naval sized nuclear plants in mass production style since we can apparently still build those and my limited understanding is their smaller size and output makes them safer (less decay heat etc). Ship those around as needed for refueling. And just have a couple dozen on each site to produce the equivalent power. It would combine a national strategic need that we have to do anyway (naval nuclear power), with another need that we seem to be failing to do (getting back on the horse with producing reliable clean power).
I don't really like that it's fluid fuel though. As I said in another comment, the unknown remote maintenance implications of that are very far from hashed out, and will very likely be terribly expensive for a fairly long shakedown/learning period. Fluid fuel is a good end goal. But don't get me talking about fluid fuel in a near-term first-of-a-kind plant with a low-ball operation/maintenance cost estimate. I also don't like that if they succeed, they have a very large waste stream of super radioactive large-scale components (that get swapped out ever ~5 years and put... where? That's gonna be a problem). Also, working primarily with a country with inexperienced/non-existant nuclear institutions for a very advanced reactor (Indoensia) is probably not going to work. I get the logic though, bootstrap a new nuclear regime without the old regulations. Problem is, fluid fuel reactors have a variety of postulated novel ways to increase source term. That will take work to license. A lot of work. Experimental work, in neutron irradiation.
I just wish they'd try a small light-water reactor with their shipyard construction experience first and take it from there.
I also freaking love that they use LaTeX.
Thanks, that's quite a story!
> I don't really like that it's fluid fuel though.
I have some misgivings about this as well. A water-soluble fuel salt in a thin-skinned (compared to a high pressure LWR) vessel on a ship, what could possibly go wrong?
(I'm a fan of MSR's and I'd love to see them deployed, but I'd prefer them on dry land thank-you-very-much)
> As I said in another comment, the unknown remote maintenance implications of that are very far from hashed out, and will very likely be terribly expensive for a fairly long shakedown/learning period. Fluid fuel is a good end goal. But don't get me talking about fluid fuel in a near-term first-of-a-kind plant with a low-ball operation/maintenance cost estimate.
Agreed, but IIUC Thorcon, similarly to Terrestrial, are planning to replace the entire reactor vessel with the primary circuit every few years (5/7/?). So AFAIK the plan is not to do any maintenance of the reactor vessel. Guess you have to hope one of the primary pumps doesn't need a new bearing 1 month after commissioning, then, eh?
> I just wish they'd try a small light-water reactor with their shipyard construction experience first and take it from there.
Yes, though it seems passively safe LWR's are quite massive. Nuscale reactor vessel is a frickin' 700 tons for a paltry 60 MWe. Thorcon reactor is 250 MWe (or is it 500, their materials are somewhat confusing?). Would a passively safe 250 MWe LWR fit on a ship, along with a pressure dome to handle a LOCA?
Hmmmm... This reminds me of the nuclear armed b52s discussed in "command and control". Are all of the failure modes actually safe? And is building a movable platform contributing to the risk of failure? Feel like for nuclear, KISS is particularly important.
The nuclear struggles with genuine transparency, which, imho, would go further than anything else to shifting the public's feelings on nuclear power.
Such as Akademik Lomonosov?
The Fukushima accident may not have caused much in the way of injury, but the cleanup is projected to cost over $100bn. It’s not so easy for nuclear power to compete when those costs are factored in.
So yes, passively safe reactors are a big deal in my book.
I would say nuclear is already competetive when compared to that.
Presume total extinction due to climate emergency.
GWP = annual gross world product.
r = estimate of risk that we kill ourselves through other means per year e.g. 1 in 100 due to nuclear war.
Presume zero growth (e.g. world growth is offset by population growth, environmental damage, discount rate).
Cost = GWP / 2r
You don't see nuclear for one reason: it's high risk with low returns. It isn't high risk because nuclear reactors regularly go bang. It's high risk because a plant has to operate profitability for 40 years in order to make a return, and 40 years is too far out so safely predict anything. 40 years ago there was no internet and global warming wasn't something we knew about. The plant going bang is just one of many things that could render it unprofitable. There could be fuel supply problems (cf Iran), or the demand could move away (eg, a aluminium smelter could close down), or a cheaper technology could come along, or an earth quake, or a tsunami.
The new designs in the article seem to solve some problems. Being tow-able means if the current market folds you can move it somewhere else for example, and being small means there is less money at risk. But geezzz - 4 years to build. In 4 years it is possible the price of solar or wild could drop by 40%.
If I were a nuclear regulator, I would not permit construction of a plant that could, by design, be a danger to anything other than itself if it lost power. I would also consider requiring existing plants to retrofit themselves to have the same property if the technology became available.
What about a plant that's a danger to others when it's running optimally within design spec, as every single coal fired plant on this planet is? Do you apply this standard to all power plants, or only nuclear?
I'm skeptical that "clean coal" will ever be cost-effective when considered purely as a source of power in most locations.
AFAIK fly ash is mostly used as a replacement for other filler (sand etc)... Using fly ash doesn't change the amount of CO2 produced per m3 of concrete.
I am struggling to understand what your point is here.
Also fly ash is generally a single digit percentage by coal weight burnt. So say 90% of coal burns with oxygen, most of which ends up as CO2 (by weight). Using the fly ash waste (from electricity generation) in concrete makes sense. Burning coal to indirectly justify making cement does not.
My impression is that fly ash involves the production of more CO2 than burning coal to produce an equivalent amount of portland cement, but it's worth it when you're burning coal anyway and fly ash is basically free as a byproduct. So in practice it essentially offsets CO2 emissions from burning coal, but only partially.
That's just the impression I've gotten though, I don't have any numbers for any of it.
PS: Nuclear also has many deaths not generally included in these statistics. As building and operating a power plant is not the only risky things you need to do to have nuclear power. Ex: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4164879/
I am a fan of nuclear but current economics seem against it even if they are driven by irrational reactions.
However, minor incremental safety improvements may be a tool in addressing this political risk - though it is true that cost still needs to be controlled.
If you can say "prevents the type of accident that happened at Fukushima", those could be powerful words. Fear is often not rational, and it's human nature to be acutely fearful of things you have seen happen (even if they aren't actually larger risks). Even if the actual safety impact is small, something that hits directly at the thing people are worried about could have a large impact on the political reality.
Yes, it's inefficient to have to placate people who don't know a lot about it, but if nuclear is to succeed, we have to realize that the majority of people are never going to understand the risks in depth. It seems worthwhile to spend some resources just to make it so "nuclear" is less of a scary word.
Is there truth to this claim?
If so, and if such failure modes are possible, I’d say that current deaths per kWh is not be the best way to estimate risk.
No, there isn't. They invented quite some nonsense to add drama and the reactors blowing up like thermonuclear bombs is among that.
https://theconversation.com/ten-times-the-chernobyl-televisi... point 5
It's entertainment, not a documentary.
What do you make of people who have been there and worked there afterwards, which came to a different conclusion? Conspiracy theo- or terrorists?
The whole point of the "docudrama" was pointing this out, but failing to point out the next level of this error.
And most of you are regurgitating the same shit over and over again, in blissfull ignorance.
So my point should have been:
The Tv show had good production values, but told the story
wrong, ignoring the new interpretations which meanwhile became available.
Then someone asks about something which couldn't even happen according to that new interpretation, because not enough molten corium in there anymore to make a good and large dirty bomb. Which could have happened IF the corium had been there in large amounts as has been assumed up until now. But it is mostly gone. So not even wrong!
Wasn't the whole point of the show to show how wrong assumptions and mis/disinformation leads to catatsrophe?
Especially in the end of the last episode? During the trial?
Likewise with the 3 plant workers on a suicide mission to open the sluice gates, who were supposedly sent to their deaths. They’re still alive and healthy today (except one who died of non-nuclear causes).
Since they did state that some of the characters were made up I had some hope they’d be a bit careful about other things, such as this claim that didn’t add that much to the actual drama.
Now obviously the nuclear explosion of the corium is not entirely impossible, there are known mechanisms which could set it up. But even if it happened, it would not erase Minsk, that is not believable, because Minsk is too far away. So that puts the main claim into question. How probable such corium explosion is is not clear, some things about nuclear bombs which those experts knew are probably still classified, but internet pundits say not very likely.
Indeed, this is what is glanced over way too often with the urge of politicians and industry bureaucrats to rush builds of the bleeding edge and experimental designs.
The only economic nuclear power stations today were big, multi-gigawatt PWR and BRW designs with more than 4 reactors. In comparison to power output/fixed costs, all other factors pale in comparison.
On the other hand a pure win would be figuring out how to enlarge the market share of nuclear by persuading those who are already willing but balk at the large up-front costs, the insurance, the regulatory environment, the long planning processes (etc. etc. – basically everything but the tech).
If the USA and the EU both made a commitment to doubling the share of nuclear tech in their jurisdictions to combat climate change (and we're going to need loads of cheap juice to power all those EVs) by streamlining the processes and creating an Atoms for Peace mark II umbrella that would make this HNer a happy camper.
Don't see it happening unfortunately. Every time this topic comes up I get so disheartened.
However it's abundantly clear that the current tech's time has come and gone. The current designs can't be constructed in the US, as it becomes a Mexican standoff between utility, designer, and contractor, each just waiting to sue the others for what they assume will be inevitable and costly delays and construction/design errors.
The Rankine cycle for converting heat to electricity is just not super exciting any more, and wind/solar/storage may outcompete thermal electricity generation as an entire class of technologies.
We no longer have the project management skills and construction skills we had 50 years ago.
If you look back at the pre-Three Mike Island track record for construction, it isn't much better than our current, and fairly disastrous construction record from the past decade. There is a survivor bias when we look around at the currently running and constructed nuclear reactors.
Meanwhile, there's a route that requires far more scalable expansion, our current path of wind, water, solar and storage.
Screw up 1% of the concrete pours for a nuclear power plant and it's a disaster.
The distributed nature of wind and solar makes building them, and training the workforce to build them, easier.
Already wind/solar/storage have beat nuclear on cost, are beating coal, and in many areas solar+storage is beating natural gas for new installs.
We don't know how much wind/solar/storage will improve on cost, but we know it will be quite a bit. We know that thermal generation of electricity is optimized to its max.
As far as dense energy production, what benefit does that have? If you want to stick a steam turbine on wheels, or a nuclear reactor in a submarine, that would make sense, but I'm not sure how it helps for the grid.
With fossil fuels, we are simply using the stored energy from past fusion.
It's likely that we will start creating synthetic fuels from the electricity that comes from wind and solar, if you want a dense storage mechanism for keeping fuel close by for mobile applications or isolated sites.
There's nothing magical about nuclear, it's just a heat source. Unfortunately it's difficult to transmit heat long distances.
So that we don't blanket the countryside with wind and solar farms? I would have thought that'd be obvious enough.
Also, very few people are really factoring in the environmental costs of repairing and recycling huge turbines and masses of solar pv panels – it's externalities like these (and other externalities besides) that are masking the true cost of renewable tech in the same way that environmental pollution masks the true cost of so-called fossil fuels.
Just you wait and see. The Chinese and Russians are forward thinking, increasing the allocation of atoms for peace in their energy mix.
Why would you think recycling turbines or panels or inverters is going to be onerous? The quantity of materials, and the nature of the materials do not seem in the least bit onerous.
I don't think this is true. We would need about 20,000 sq mi of solar to cover just our electricity needs today. Problem is, electricity is only ~38% of our energy usage. To replace all energy used (transportation, heating, industrial, etc) we need something more like 53,000 sq mi of solar. This would be like covering all of Iowa or New York with solar. Since panels only last around 30 years, we also need the infrastructure to produce, install, remove and recycle ~1,750 sq mi of solar panels per year.
And I bet it would actually be a fair bit larger because of all the extra infrastructure you'd need to produce, process and recycle the solar panels. For some reason nuclear waste is a very big deal but wind and solar never appear to have any externalities. Funny that.
Imagine covering all that land with forest, or growing vegetables?
France is well known for nuclear being a high percentage of its electricity production. 75% – how many reactors? 58. Only 58!
I can't find your stat for asphalt. The one I found was: https://www.quora.com/How-much-land-in-the-United-States-is-... which says, “The estimate of roads in America is about 65000 square miles but Maybe 8% of that isn't asphalt. Plus This number would not include parking lots, driveways, private roads and other uses.”
I think an energy production source that takes up as much land as roads _is_ a huge amount of land. Imagine taking each road and covering some land somewhere in the equivalent amount in space with solar panels. That's mind-boggling.
> doesn't even directly produce revenue.
So what? Infrastructure doesn't directly produce revenue. Yet it enables all sorts of revenue generation. What sort of argument is that? You know what else doesn't even directly produce revenue? Electricity production.
Why is it an enormous amount of land to cover for electricity? Iowa is already 100% covered with farms, which use the sun for growing things. And we have 30x more land covered just for farming, much of it make-work to ensure that we have a massive oversupply of field corn and soybeans. Solar panels are a far less intensive use of the land than that sort of farming.
Why is only 58 sites for France's nuclear reactors a good thing? Can you connect to some sort of value system where such a count becomes a good thing?
My point about "doesn't even produce revenue" is that we covered up all that space without any sort of direct financial incentive to whoever lost that land; with solar, farmers can, and are, devoting their land to electricity production because it's a positive revenue stream for them.
I'm also having trouble contemplating the problem with solar panel waste. What problem do you think is created by that disposal? Logistics? Environmental?
"Mind boggling" could describe any of the industrial processes that happen every single day in our modern society. One could look at the vast amount of corn produced during harvest, and think "that's unbelievable," but it's not an argument against doing it.
Now, maybe in the densest parts of Europe things could be different. This just means that in a renewable future, energy intensive industry leaves Europe. Europe going nuclear would not change this, as they still couldn't compete with the sun-drenched countries closer to the equator.
- waste mgmt
- proliferation risk
(for uranium-/plutonium-based reactors,
not so much for thorium-based reactors)
- outrageous construction costs
- heat pollution (heat discharge into local waters)
- slow to blackstart
The only good things about nuclear are that the fuel is cheap (maybe) and it has no air pollution (barring accidents). That's not enough to justify the issues.
Energy storage is much less of an issue if you can simply produce more than you need to offset e.g. cloudy days and use the excess energy to synthesize any of a wide range of fuels that can be stored, top up batteries, pump water to some reservoir, or power any of the many ways in which we can store energy. People are getting creative when it comes to energy storage. Energy storage cost is dropping rapidly as well.
Nuclear doesn't just need to get safer, it also needs to get vastly cheaper to keep up with this. IMHO if you are not designing for half a cent or less per kwh, you might as well not bother. My understanding is that current designs are off by factor 10 at least. At those prices, even the security needed to protect the facilities will be prohibitively expensive.
On the other hand, something like the NuScale design takes an all-passive approach: it places a smaller fission core directly in a massive swimming pool that has enough water to passively cool the design all the way down. There are no moving parts to switch on in the case of failure. The way you handle a catastrophic failure is: you do nothing. It solves itself.
No moving-part safety mechanisms to install, just a big tank of water. No fallback mechanisms for those safety mechanisms, etc. Inspection is pretty easy: did the water level remain in range? Yes/no.
Cutting costs of safety inspections due to an inherently safer design doesn't mean a less-safe outcome.
Don't know about others.
For a technology where the prices are decreasing, this is harder to do.
Something that see nobody discussing and that I gave almost no thought to myself is the embedded carbon cost of the mining and enrichment of Uranium itself.
Never mind the building of the plant, etc., but the actual carbon expended to achieve a workable fissionable fuel.
This process was brought to my attention in the long, detailed chapter on Uranium enrichment in _No Immediate Danger: Volume One of Carbon Ideologies_ by William Vollmann.
It's really quite amazing how many steps are involved and how expensive those steps are in terms of embedded carbon cost. In the absence of fully non-fossil-fuel power sources to do that mining and enrichment it is difficult to see how that process makes any sense absent the massive economic and military subsidies we have in place for gasoline/diesel.
Something like lower property taxes would do. Or free electricity and heating for all residents.
Nuclear fails because the public is uncomfortable with these plants, not for any technical or cost reason. Though to your point you could avoid spending the R&D on safety technologies and instead spend it on marketing which would likely yield better results.
It’s a third rail after Chernobyl and 3 Mile Island, the public perceives it as far too risky to allow anywhere near them. No one wants to touch the idea and yes, it doesn’t help matters that nuclear is insanely expensive.
And of course if you fit the panels at the same time as building the house you don't get any additional deaths and even rooftop solar sails to the top of the list.
I'm sure we'll find another obscure stat to focus on though (even if we have to leave off anything that beats nuclear). Dont let the facts get in the way of a good story.
The onerous safety regulations are mostly the reason nuclear plants run over budget and schedule. Safety improvements that can relieve some or all of that burde arr probably worth it to scale nuclear.
You could probably remove quite a lot of requirements and still have the safest energy generator and that would bring down the cost.
Safer nuclear power is not just about reducing the possibility of immediate death, which, of course can't be entirely eliminated. You still have risk to employees from non-radiological parts of a power plant.
What you won't have from safer nuclear power plants is the risk of spreading stuff like Strontium 90 over a wide area. That by itself is a very valuable goal that will vastly reduce the maximum downside risk and the cost of mitigating that risk.
Cost is part of risk, in the form of financial risk. Smaller, less expensive plants are less likely to become white elephants on rate payers' bills. They won't lead to To Big To Fail entities that may need bailing out because they are the custodians of a big nuclear mess.
Safety is multi-dimensional. People opposed to building more nuclear plants with current technology understand that. They want to keep their wallets safe AND their milk safe. They want to keep the value of their property safe. That's perfectly rational.
No. Safety depends not only on deaths but on all kinds of damage. It also does not depend on how many people nuclear kills per year. That number is predictable so it isn't even a risk (to society), it's a cost.
Nuclear is unsafe because of the damage it causes in the worst case. What happens when NPPs are operating correctly isn't even relevant to the discussion.
In 2019, we have to consider that even advanced democracies with great scientists and technologists might descend into some form of illiberal rule. Imagine if you could not depend on leaders to shut down a plant if problems are discovered, or if contracts were awarded based on cronyism, or if it was impossible to guarantee the quality of materials, or if whistleblowers were not protected.
I'm not sure anyone can guarantee that any country will definitely remain stable over the lifetime of a nuclear reactor. Black Swans are out there.
This is the number one thing that nuclear power advocates seem to ignore.
There isn't any need for active cooling since the nuclear reaction is thermally regulated. There isn't any pressurized water that can blow the top off a containment vessel. Even if there is a breach it doesn't blow waste across the countryside because there is no pressure difference between inside and outside the reactor.
China, India, USA, Russia, France, UK, Pakistan, and Israel already have nuclear weapons. If you look at the fraction of world energy that that set of countries and their collective military allies uses (nevermind Israel), you can feel pretty good about transitioning more to nuclear even given a non-zero risk of proliferation.
Thorium is also more abundant and easier to work with. The only reason why we have an uranium/plutonium nuclear industry is because those fuels permit dual-purpose (weapons generating) designs. Now it is just industrial* inertia.
Edit: *industrial and regulatory.
But there's a problem. Pa-233 is a strong parasitic neutron absorber. So when it's sitting there for 26.8 days, if it were still in the nuclear core it would poison the chain reaction. So what people plan to do is to pull it out of the core chemically and put it into a holding cell outside the neutron flux where it can decay to U-233 in peace. Then the U-233 is added back to the core as it arrives.
The U-233 is a potent nuclear weapons material and can be extracted from the decay tank in what are called in the non-proliferation industry "Significant Quantities". Faced with this issue, the ORNL folks created the Denatured MSR project in the death throes of the MSBR program (~1960s) which had U-238 mixed in to denature the WG U-233. Of course, then they were producing plutonium...
The general claim is that U-232 is also produced in trace quantities, which has Tl-208 way down its decay chain, which emits a massive 2.6 MeV gamma ray that's hard to shield. Since it's way down the decay chain and U-232 has a 69 year half-life, every time you chemically purify your uranium you have pretty small amounts of gamma emitters. So you can purify, assemble a weapon, and drop it in a few weeks without worrying too much about Tl-208.
The thorium-cant-make-bombs thing is a total myth. All nuclear reactors need safeguards, even thorium-fueled ones. This is doable and should not prevent us from making more carbon-free energy with any kind of nuclear reactor.
More abundant: meh, not really. There's uranium dissolved in seawater in vast, practically infinite quantities.
Easier to work with: definitely not. Higher melting temperatures for ceramics make solid-fuel thorium harder to fab, and the fluid fuel stuff is int he R&D stage. It also leads to lower-density fuels, which are crappier neutronically.
U-233 is unequivocally excellent weapons material. That's undebated fundamental nuclear physics. A Significant Quantity of U-233 is defined as 8 kg, better than U-235!  The folks down at Los Alamos aren't messing around.
Just read this: http://fissilematerials.org/library/sgs09kang.pdf
The engineers were very optimistic about selling this even as small municipal thermal power plants (for heating water) very close to city centers. The idea of passive safety is quite beatiful, but it seems
no PIUS reactors were produced. Rosatom seems to have had some success.
More info about PIUS can be found at
Nuclear power was invented. A few nuclear accidents happen. The solution was to put more regulation in place. Regulation increases costs and limits reactor designs (large plants, conservative / pre-existing design).
End result? It's impossible to build "safer" reactors, because they're economically uncompetitive under the regulatory burden designed for older reactors. And the regulations never change because no one builds anything but old-style reactors.
I understand the DoE and other similar organizations have prototype programs, but from results evaluation they seem to have gaps in the path to production.
Essentially, we're letting 1960s nuclear fear of 1960s reactor designs write our regulations instead of science.
If you want nuclear, you want punitive carbon taxes, or carbon trading with low caps.
I think this is the crux of the issue. Carbon-emitting plants get a free pass on safety and long-term environmental costs, while for nuclear all those things are examined with a fine-tooth comb, then compared to the cost of alternatives without those things.
In any regulatory regime that punished carbon emission the same way it did nuclear waste, nuclear contamination, etc, then coal plants would be unthinkable.
I was going to say "then nuclear would be obvious", but I'll hold judgement there because I don't know how that would compare to other non-carbon-emitting sources (hydro, solar, etc).
That doesn't mean they are less bad than nuclear plants but the claim that they are unsafe is just wrong.
By shifting the regulatory cost from focusing on lesser risks to catastrophic ones, you could make fundamentally safer reactor designs economically competitive while still retaining the primary political goals (avoidance of major event).
I'm concerned but not running around screaming if a reactor leaks tritium. I'm very much the latter if a reactor goes prompt critical.
In the same way I wouldn't offer SR-71 insurance.
That feels like a dodge on the part of regulators.
Thanks for the pointer! Will be an interesting read.
This is fairly cheap, a few hundred million, and in terms of safety it's a no brainer, because the US already has nuclear waste that needs long-term storage.
If this can't be solved, it seems almost pointless to dream of new reactors.
I have to wonder why burial was being pushed so hard, so early. Maybe they were worried surface repositories would be targets for ground burst nukes in WW3?
Left on its own, halted thermal reactor generates hundreds MW of heat after shutdown. That heat destroys cladding of fuel, generates explosive Hydrogen and causes meltdowns of former core.
It is believed that ATF, core catchers and electricity-independent passive cooling will reduce risk of this types of incidents, commonly called LOCA - Loss of coolant
There are only 31 nations in the world that has nuclear power.
If, in the unlikely case, we successfully distribute the nuclear technology to the rest of the world. How do we prevent/contain states go rogue and start enriching fuels for nuclear bomb?
This might be a harder problem to solve than technology break through.
By using different fuels. The fuel we currently use (enriched uranium) was chosen because we could also use it to build weapons. A different fuel (i.e. thorium, etc) could be used that couldn't be used in making weapons.
This question aside, I feel states can not resist the temptation to get nuclear bomb technology: It's a great equalizer for power. Looking at how North Korea was able to repeatedly get U.S to the bargaining table, I think none of the nuclear powered country would want any other country on Earth to gain such technology.
Oh, and it doesn’t produce the greenhouse gases that are currently threatening global stability in a timeframe of decades.
We shouldn’t minimize a technology’s shortcomings, but we should at least frame it fairly and soberly among our set of options.
Whether actual reactors get built is another matter.
It's easier to secure a massive plant than a thousand small ones.
Imagine the outcome of some underpaid and overworked cable runner digging into a buried mini-reactor with a JCB digger. Or a trucker falls asleep at the wheel and drives their Mack truck through an above-ground reactor.
The difference is between the media coverage being "Idiot drives truck into nuclear facility, is arrested, no damage" and "Idiot digs into mini-reactor, irradiates neighbourhood".
And that's before people start yelling "Not in my back yard!"
I think your last reasons are probably more influential. Nobody knows or seems to care much about sites like where the above incident occurred. And so far such incidents have been fairly contained, at least in the U.S. In some other parts of the world neighborhoods do become contaminated on rare occasion.
Tiny, safe, low-cost reactors are a better fit for off-grid power and heat in remote areas.
Though of course aside from not quite existing yet and probably needing a smart grid to coordinate properly these will take full-bore hits from NIMBY.
There are plenty of sites that would be happy to host nuclear, if it were possible to build. Vogtle and Summer are our recent examples, and NuScale is deploying soon too.
NIMBYs have not held back nuclear as much as the industry itself.
I'm surprised the (US) military isn't looking into these more.
I would think it would reduce /simplify the logistics of hauling diesel for generators over hell's half-acre.
One issue was that small-package reactor designs of the 50s and 60s required highly enriched uranium... which doesn't seem like the best idea to leave lying around at (by definition) remote outposts.
What he may have been talking about is activation of troublesome elements that cause contamination that interferes with access. A prime example of this is the wear resistant alloy Stellite, used in valve seats. It's an alloy of cobalt. Some cobalt does wear off, gets circulated through the reactor, and is transmuted to 60Co, which increases the radiation field around all the piping.
All the materials in your reactor that are exposed to neutrons need to be purged of troublesome trace elements that can cause this sort of activation.
It has to do with strict traceability, design validation, and testing-proven performance more than it does anything about nuclear aspects.
I wonder if there's potential for a similar approach here?
Two experimental reactors of this type have worked in 60s, but technology was abandoned because it didn't produce the isotope of plutonium used in nuclear weapons.
Fluid fueled reactors, mostly in the form of Molten Salt Reactors (MSRs), of which the LFTR is one brand name of, do have lots of potentially huge benefits in terms of simplicity, online refueling, and straightforward reactivity effects. We do only have about 5 reactor-years of experience with them, and so we don't fully understand the costs of building, operating, and maintaining such systems in today's regulator regimes.
There is some reason to be concerned. When the fuel is dissolved in fluid, the radioactive fission products are dispersed everywhere. Literally half the periodic table of the elements is in there, and lots of it is volatile and mobile. It gets on your pumps, your valves, your heat exchangers, etc. Doing routine maintenance becomes very challenging and will need to be done remotely.
A line I heard recently regarding MSR maintenance is: "You'll need robots to do the maintenance of your maintenance robots." Another memorable gem is "If you can make robots that can do that, you should just sell the robots"
We should absolutely work on progressing this technology, but in the face of a climate disaster, we should just build more of what we know is already safer than almost every kind of energy system we can deploy, which is regular Gen III LWRs. We need to solve problems on the construction yard so we can build them much more cheaply.
How do some of the other alternatives like Pebble Bed fit into this?
I imagine PBRs would be more challenging to recycle fuel as it's combined with the moderator(?), but are there other issues which make it unrealistic compared to traditional PWR/BWR/LWR/Magnox reactors?
Second, the fuel particles you mention are very expensive to fabricate, $10k/kg. Estimates of future costs go "as low as" $3k/kg, but some say it could even go up to $30k/kg. In all cases, that's really expensive fuel fabrication. There's a plant in China that can fabricate them in moderate bulk right now, so perhaps with time and experience we can figure out how to bring this process down in cost.
Aimed at solving power density and decay-heat cooling issues, there's also the salt-cooled version of the pebble bed reactor which gets the high-temperature fuel benefits and trades high-pressure gas for low-pressure salt. A research group from MIT and UC Berkeley has worked on this for years under Prof Charles Forsberg, and a company in the Bay Area called Kairos is now working on commercializing it. Unfortunately you get a lot of tritium production from the best known salt, which is a FLiBe salt, where the Lithium + neutrons results in crap-tons of supermobile tritium. You can cold-trap most of it but it's still a pain. And the fuel is still $10k/kg to fabricate as far as anyone knows, and the graphite cracks, and high temperature corrosion under irradiation is hard.
Maintenance of MSRE was done by humans without much downtime or exposure. Ease of maintenance is a function of design. Just design it carefully.
A lot has changed since MSRE ran, and MSRE was a fairly simple experiment to prove a concept. It didn't have all the systems necessary to make practical energy, and so it didn't have the maintenance issues you'd expect. Also, it only ran for like 5 years, vs the 60-80 we're hoping for these days from these facilities (inherently requires lots of maintenance).
Have you ever done work planning for ALARA at a light water reactor? Those who have raise eyebrows really high when academic reactor designers start saying how easy the maintenance will be. Admiral Rickover's quotes from 1953 just keep on coming back to haunt us . He didn't curse us to death, but he sure warned us that we need to be working really hard on new/effective solutions to these kinds of problems. Most advanced nuclear advocates skip over these points.
RE: Design it carefully: This takes practical experience. The number of people today designing new reactors who have this kind of experience is very close to zero. We will have to re-learn.
"Exposure of personnel to radiation has been held well below permissible limits: the maximum exposure of any individual in any quarter has been <0.5 rem." This is within the ALARA standards.
RE: no real fluid-to-fluid heat exchanger.
MSRE had salt-to-salt and salt-to-air heat exchangers made from hastelloy-N.
RE: or power conversion cycle, which is where lots of maintenance troubles arise from.
That's the part which is not highly radioactive. Fluid fuel reactors have simplest fuelling mechanism of any reactors. The fuelling of a fluid-fuel reactor is even simpler than fuel injectors of diesel engine. Where the need for "maintanence" arise in this simple machine??
Only moving parts are the pump impellers and the control rods. ORNL had some difficulty designing the bearing, seals etc. for the salt pump. But, even that is solved today with concentrating-solar salt pumps.
Ah, the good old days! 25-50% of the radioiodine from MSRE is completely unaccounted for. No one knows where it went. This is wholly unacceptable from a modern regulatory approach. It will have to be found.
> MSRE had salt-to-salt and salt-to-air heat exchangers made from hastelloy-N
Fair enough. It's generally in the salt-to-water heat exchanger where major maintenance concerns take place in a power reactor. Check out steam generator problems in PWRs and SFRs to see what I mean. You're right that the radiation will be low there if they use an intermediate salt. But the baseline maintenance problems come in at the steam generator in most plants. So MSRE avoided any problems there but any power MSR will have them like any other reactor. Good old BWRs get around this via direct cycle.
> Where the need for "maintanence" arise in this simple machine??
Pumps. Heat Exchangers. Valves. Flanges. Welds. Vessels. Graphite. Reflectors. Fission product processing equipment. Instruments/sensors. Control mechanisms. There are very complex systems with lots of things working together in a very tough environment (high radiation, high temperature). Maintenance is a major challenge.
<0.5 rem per quarter (or 5 mSV) is in compliance with today's dose limit. ORNL was a competent American national lab with high standards even back in the 1960s. Another hollow argument from today's incompetent nuclear industry.
"Exposure of personnel to radiation has been held well below permissible limits: the maximum exposure of any individual in any quarter has been <0.5 rem."
"The maximum annual dose allowed for radiation workers is 20 mSv/yr" https://www.world-nuclear.org/information-library/safety-and...
135Xe also can be removed (halflife ~9.2 hours). It is famously a very powerful neutron poison with important effects on reactor operation; those advocating thermal breeders count on it being removed before it soaks up neutrons. But this leads to an increase in production of its decay product, 135Cs, which has a halflife of 2.3 million years.
Despite a long-standing agreement among many experts that geological disposal can be safe, technologically feasible and environmentally sound, a large part of the general public in many countries remains skeptical. from: https://en.wikipedia.org/wiki/Deep_geological_repository#Pri...
In fact, not only are the dozens of needed DGRs not being built, in many cases fuel which has cooled enough to be moved into cask storage is instead still sitting in actively cooled pools. So not only have we not built any large DGRs (other than that under construction one in Finland), we haven't even taken the intermediate step of preparing spent fuel for any form of passive storage.
Look at Germany quitting on nuclear and using coal power plants instead. Look at France producing relatively cheap and low-carbon energy using mainly nuclear power plants: https://www.electricitymap.org/
This is one of these conversations like GMOs, like vaccines, like herbicides, like so many others where it seems that rational conversation is impossible because only extreme viewpoints can be heard. Nuclear is incredibly dangerous when it goes wrong but the risk can be managed and when it works well it's very competitive. Of course the costs of properly dismantling the reactors and storing all the radioactive waste needs to be factored in. It's a tough engineering problem but compared to rising sea level and massive perturbations in the climate it seems a whole lot easier to manage.
I'd much sooner live close to a nuclear power plant than next to a busy highway.
Deep geological waste repositories are fine. Lets get those operating safely so we can answer the "what do you do with the waste" problem definitively and then move on. Reprocessing may make sense again sometime in the future but for now we need the prereq of deep storage. I agree with Frank von Hippel in this case .
At the moment, no. But the economics are likely to change over the next century or so. Which means that reprocessing should definitely be taken into account when determining how long spent fuel needs to be stored. Requiring storage facilities to be good for ten thousand years or more is not reasonable given that it will be economical to reprocess it long, long before then.
Check out all this seawater extraction progress .
however, neither your link nor anything from a reputable site that i've found through google says anything about costs or current industrial production. do you have any data to back up your claim of low cost, or is that claim purely speculation on your part ?
unless there's data that i've missed, it doesn't sound like seawater extraction is currently economically viable
We're comparing long term scenarios here: reprocessing vs. seawater extraction. The reprocessing + hot refabrication process has been done and is extraordinarily expensive. If seawater extraction at scale is indeed viable, it's long term prospects in my view are way better than reprocessing.
You'd need a really reliable launch process like a space elevator to do this without worrying about dispersing it around in the atmosphere. It's worth talking about but it's hard to imagine a socially-acceptable pathway at the moment. Deep geologic repositories are safe and known. We should just use them.
1. No one does that, or has the ability to do that except the Russians 
2. Much less hazardous is still tons of extremely dangerous stuff that will last 100 k years. 
 fast breeders. I know you can re-process fuel for normal nuclear reactors. But that doesn’t give you: “less hazardous and only needs to be stored for a much shorter time” waste
 to a first approximation linger lived isotopes are less dangerous. But the conclusion that they’re not a problem is not correct:
- An isotope that lives 100k years is incredibly radioactive!
- these isotopes can produce children that are very short lived, and therefore nasty (think short lived radon, produced from geologically decaying isotopes)
Edit: spelling of “extremely”
I am not very familiar with the Russian breeder design in particular, but generally that is wrong fro 4th generation designs:
"...Fast reactors can "burn" long lasting nuclear transuranic waste (TRU) waste components (actinides: reactor-grade plutonium and minor actinides), turning liabilities into assets. Another major waste component, fission products (FP), would stabilize at a lower level of radioactivity than the original natural uranium ore it was attained from in two to four centuries, rather than tens of thousands of years"
While there are issues with nuclear power, the worry people have about nuclear waste is greatly overblown to say the least. The amounts being generated are manageable and in a relatively short amount of time we can use most of this "waste" to generate electricity.
Yes, the west has done research and maybe a couple of demo reactors of insignificant power. But only the Soviets, and then the Russians have an industrial sized “fast”, or “breeder” reactor.
As to the waste of “breeders” being manageable, that remains to be seen, doesn’t it?
Granted that the power level for EBR II was insignificant compared to a commercial reactor, but it did run successfully for about 30 years and generated about 2 billion kilowatts of power.
>...As to the waste of “breeders” being manageable, that remains to be seen, doesn’t it?
Within about 4 centuries the small volume of waste generated by a breeder reactor should be less radioactive than the uranium ore that it came from.
Double digits of France's electricity comes from reprocessed nuclear fuel.
The nasties are all there still.
Breeders “make” their own fuel from actual waste. The US and France had reader had breeder programs, but shut them down.
How many would actually be needed to burn up the unused fuel of "regular" reactors? Is there some ration of regular:breeder that would be needed (5:1, 8:1, 13:1)?
> to a first approximation longer lived isotopes are less dangerous.
But isn't the shielding required for the longer lived stuff simpler? Presumably the short-lived stuff is hotter gamma radiation, which needs more shielding.
Edit: according to Wikipedia, cesium-137 decays to barium-137m, which decays to barium-137 by gamma ray emission (https://en.m.wikipedia.org/wiki/Caesium-137). So even though cesium-137 decays through beta radiation it needs shielding against gamma radiation.
Depends on the specifics, e.g. Russia is proposing a 2:1 ratio for a cycle they're planning:
ALMR reactors would use that waste to produce short half-live waste which radiation can even stop in the matter of hours...
Thats what Chinese invest into now and technology is 40 years old.
Technologically we are way past the "dirty&dengerous" nuclear reactors. ALMR also fixes issue of old nuclear reactors that could be shut down overtime.
People fear the second Chernobyl.. thats that why we dont invest into Nuclear Power that is our only chance in current age. There is no logic in that, only mass media, lobbing and disinformation going rampant..
‘S/sodium/whatever other metal you prefer/‘
It's a tragedy..
Its completely illogical to block Nuclear Power advancement, but goverments are either lobbed or public opinion disagrees after being fed complete horseshit disinformation.
The US’ got lazy, the European was good, but never innovative, Canada and S. Africa are too small.
Um, what? France has been reprocessing for decades.
> Much less hazardous is still tons of extremely dangerous stuff that will last 100 k years
Um, what? What's left over after reprocessing is only dangerous for 100 years or less.
100 years for reprocessed waste? Do cite!
Oh really? Which isotope among the fission products would that be?
(ALMR tests performed in USA already confirmed what you asked for and that was 1984..)
So … where's it in production yet? The reasons why it hasn't happened might be instructive for learning why this problem is harder than it might seem.
I look at it as a tragedy. Oil Industry is like a cancer to our society right now.
The truth is more mundane (and you should have realized something was wrong when you started thinking in conspiracy theories). The technology is simply not as great as you think it is, and like most technologies it's probably not going to win. There's no dishonor in that; the market is a brutal place.
Water absorbs almost all harmful radiation within a few meters
The thought process behind just throwing barrels into an ocean trench as was done by the US was and still is sound but people are freaked out by the notion. The UK was encasing barrels in concrete before doing the same which is more than good enough by most measures.
Ultimately nuclear waste is easier to deal with than some other toxic industrial waste or chemicals.
Nuclear waste sitting at the bottom of the ocean will have a hard time ever reaching the atmosphere.
And wouldn't it be more efficient to spend the money on energy technology that has none of the problems and is carbon-neutral?
The potential for renewables in the US is fantastic.
For solar alone a recent report states:
The total estimated annual technical potential in the United States for urban utility-scale PV is 2,232 terawatt-hours (TWh).
Full report at
It involves significantly less.
Nuclear power generates significantly more energy for the amount of resources used.
Intermittent renewables (in scenarios shy of wanton overbuilding) result in deficits, which requires energy storage to address. Energy storage (aside from pumped hydro) is pretty carbon-messy.
Surplus, on the other hand, can be bled off into energy-negative carbon sequestration.
There's obviously lots of other points, but it's mostly fair under economically realistic scenarios.
- easy storage
- constant availability
- cheap construction per MW/h
And we cannot afford to pollute our environment even more burning fossil fuels.
So, you bring up an interesting point with cost per mwh. Nuclear is not nearly cheap enough to be competitive right now and would have to come down by magnitudes to out-compete solar/wind + storage in a few decades. I'd say a good price to shoot for with new nuclear designs that might still be too high would be around 0.1-0.5 cents per kwh in a few decades. That's only 10x less than current bids; you'd probably want to stay below that even. But anything over that would be dead on arrival in terms of profitability.
And I think we are way past the point where thinking about profitability should be our first concern.
ps. I find it hilarious when people talk about renewable energy sources but dont take into consideration energy storage. Batteries production may go down in price, but that doesnt change the fact how toxic that production is to environment and how big of a footprint it leaves for the future.
Building new nuclear powerplants is not the way to do that.
Solar panels production has very bad impact on the environment in different areas than CO2 and those panels are worthless after 10years. Smelting parts for windturbines has the same issue of huge amount of turbines which require maintenance and take alot of space to place them correctly.
All of those technologies have serious drawbacks. While nuclear powerplant using new reactors has only one - its expensive to build but will last a century or more.
It could make sense to continue to operate existing nuclear power plants while taxing carbon emission, but the CO2 tax needed to justify new nuclear plants would be outrageously high. Long before that level of tax was reached renewables would snipe the market.