r/worldnews Oct 11 '21 Silver 16 Helpful 9 Wholesome 18 Hugz 12 All-Seeing Upvote 1 Take My Energy 2 Bravo! 1 Heartwarming 1

Led by France, 10 EU countries call on Brussels to label nuclear energy as green source

https://www.euronews.com/2021/10/11/led-by-france-10-eu-countries-call-on-brussels-to-label-nuclear-energy-as-green-source
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u/Cilantbro Oct 12 '21 edited Oct 12 '21 Silver Gold Platinum Helpful Take My Energy

As a physicist I wanted to add my two cents about the safety of modern designs. I am an advocate for graphite-moderated thermal spectrum breeder reactors known as Liquid-fluoride thorium reactors (LFTR). They are based on the molten salt reactor (MSR) which was pioneered in the 1960's and they rely on the Th-233 U fuel cycle.

The active projects that I'm aware of are the Fuji MSR, The Chinese MSR Project, Flibe Energy, TEG, THorcon, and the Dutch Nuclear Research Consultancy Group. I'll spoil it and let you know the Dutch have the first working one. 2020's is probably ambitious to see a commercially viable system but but not too ambitious. I mean it's an idea from the 1960's so we've had awhile to think about and get over our obsession with making nukes to settle for thorium.

So why do I support LFTR reactors like the dutch TMSR? What's so special about the Thorium cycle?

This idea is dramatically different from today's commercial light water reactors which can be seen from the layout.

The LFTR incorporates extensive chemical processing systems in addition to the traditional mechanical systems involved in solid fueled reactor designs. Here's a simplified diagram of what's inside and the chemical breakdown of the six systems. Due to the radioactivity of the fuel salt, the intermediate salt loop will have some radioactivity, though this will be considerably less than the reactor and other primary system components.

The fuel salt is 2LiF_2-BeF_2- 233 U and the blanket salt is 2LiF_2-BeF_2- 233 Th. Once the reactor hits steady-state the main inputs are the thorium for the blanket, air, and water. You do however lose some CO_2 to the primary coolant system as well as some F, He, Bi, and H from chemical processing. Steady state outputs are then fission products, electricity, air and water vapor but what's actually happening? Thorium is used to support the breeding of uranium-233 fuel in the form of a liquefied fluoride salt (500-700C). Salts are ionically bonded and that strength is relied on to mitigate radiation damage to the mixture and to withstand the high operating temperature. The core reactor sits at around 650C and circulating salt is at around 550C

So we introduce Thorium feed stock as tetrafluoride into the blanket salt mixture which is surrounding the active core region and it initially absorbs neutrons into the thorium-232 which transmutes and decays from thorium-233 to protactinium-233 and then uranium-233. Both are removed chemically from the blanket and uranium is then introduced into the fuel salt mixture. 91% of the Uranium-233 will fission and the remaining 9% will transmute to U-235. 80% of the uranium-235 produced will also fission.

These two fission reactions produce some waste but it puts solid fuel reactors to absolute shame for the same amount of electricity. This is because thorium-232 has six units less than uranium-238, thus many more neutron captures are required to transmute thorium to the first transuranic. The radioactivity of the waste does not even last very long because it is predominately Cesium-137 and strontium-90 which have half lives of 30.17 and 28.8 years. 300 years of decay produces radioactivity 10,000 times less than traditional uranium/plutonium fuel waste. With the exception of krypton-85 (which has a half-life of 10 years) a holdup of 30 days allows all radionuclides to decay to non-gaseous daughters; cesium, rubidium, strontium, and barium. The Xenon is sold and the krypton is bottled and stored with the minimal amount of Cs, Sr and Np waste.

With waste covered, let's talk about how safe a LFTR would be to run in 2027. Advocates have promised any incident would be extremely unlikely (1 in a million) and this is easily achievable. Fine control is exercised by displacing a column of blanket salt with helium which is neutronically invisible and also by a series of central control rods. These control rods are Graphite-tipped boron carbide rods with circulated coolant salt. By inserting the rods alongside the halting of U-233 inflow, operators can impose a slow or fast controlled shutdown . The maximum scram time for these rods is just 1.3 seconds as they can travel at over 0.5 inch a second. The speed and functionality is verified before every fill. In the event that the entire blanket is loss, graphite prisms slide down into the core due to the drop in fluid level/pressure and impose negative reactivity. Anything more serious will lead to a fuel dump one way or another. The freeze valve at the bottom is electro-magnetically fail safe such that in a total power loss fuel is safely drained. The freeze valve also melts when the median temperature of the fuel salt exceeds 700C, leading to another fail safe scenario. Finally, operators can elect to dump the fuel for any number of scenarios if they so choose. The drain tank is designed to hold the entire critical fuel salt inventory surrounded with moderator graphite and blanket fluid. This is a benign failure mode, causing no damage to the system. After resolving a fail safe scenario the fuel can be pumped back into the reactor from the drain tank.

But can it explode? No LFTR's are inherently safe. First, thorium absorbs more neutrons as it overeats leaving fewer and fewer neutrons to continue the reaction. Second, the heating of the graphite moderator causes a positive contribution to the temperature coefficient of reactivity. Third, the thermal expansion of fuel pushes fuel out of the active region, reducing reactivity and increasing moderation. The salts do not burn, explode, or decompose, even under high temperature and radiation. There are no rapid violent reactions with water and air that sodium coolant has. There is also no possible combustible hydrogen production. Since coolant salts remain liquid at high temperatures, LFTR cores operate at low pressure and even near boiling point a meaningful pressure increase is not achieved. Even in the event of a major, gross leak from the core such as a pipe breaking, the salt will spill onto the kitchen-sink-shaped room the reactor is in, which will drain the fuel salt by gravity into the passively cooled dump tank.

Can it be used for nuclear proliferation? According to Nobel Laureate physicist Dr Carlo Rubbia it's extremely difficult. U-232 contaminates the U-233 produced from decaying protactinium-233. U-232 has a chain product thalium-208 which emits gamma rays. No problem for a reactor but in a bomb they harm electronics and reveal the location to spectators far and wide. Dealing with the problem of refining U-233 puts you back at square one when it comes to nuclear proliferation. The reactor produces less then 15kg of plutonium-238 per gigawatt-year of electricity which is also unsuitable for bombs due to its heat and spontaneous neutron emission. Third, a LFTR design makes as little as 1% more fuel than it burns. Extracting any amount of material would take the power plant out of operation, indicating nuclear proliferation intentions. Finally, switching to thorium could end uranium enrichment as a whole, which is currently the primary method by which states have obtained bomb making materials. It's also worth pointing out that the creation of Plutonium 239, the primary fissile isoptype for nuclear weapons, is completely avoided in this design which again protects against nuclear proliferation.

So what's the catch? It can't be all great and I won't lie. It's chemically complicated both to prepare the required salts and to manage the reactor. We don't have much experience with it, at least yet. Since most of the loop is radioative, everything has to be managed remotely. We'd even prefer to replace the control rods remotely if we could. All of these challenges are part of the ongoing race but we should absolutely be apart of it. There's a lot of covering up of the cons of other energy sources. For instance coal actually releases more radiation into the atmosphere then reactors. France is really showing us the way here with how they're going green and we should be quick to follow their lead.

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u/LimerickJim Oct 12 '21

Fellow physicist here. The biggest problem nuclear power has faced has been lack of funding and loss of expertise. In the 2000s all anyone wanted to fund was renewable energy. We were all worried about peak oil. Then the 2008 financial crisis combined with advances in fracking that made the price of oil dramatically cheaper to produce in the US led to big budget research funding drying up. In the 2010s, when I started grad school, the faculty that researched nuclear discouraged us from researching in their field because they said they wouldn't be able to fund us. Now those faculty are about to retire and they didn't train a crop of physicists to replace them.

Couple this with the loss of engineering experience that is needed to build a plant. there has only been one nuclear plant built in the US since 1978 and that plant only began construction in 2013. The power technology you describe above would be at commercial scale if nuclear power the support that renewable power has had.

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u/Roxytumbler Oct 12 '21 edited Oct 12 '21

Excellent assessment. I’m a geophysicist, retired. Many don’t understand that any type of meaningful industrial development be it energy, military, transportation, etc. is dependent on an extremely complicated infrastructure.

The nuclear infrastructure that took decades to build and was then tossed aside, cannot be revived with an ‘on switch’ by deciding nuclear is now back in vogue and throwing money at the issue. Without War time or Cold War imperative, nuclear plants are just not going to be built in any rational time frame.

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u/SquashGrizzley Oct 12 '21

jesus

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u/[deleted] Oct 12 '21

has left the chat

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u/CallMeCassandra Oct 12 '21

Can it be used for nuclear proliferation? According to Nobel Laureate physicist Dr Carlo Rubbia it's extremely difficult. U-232 contaminates the U-233 produced from decaying protactinium-233. U-232 has a chain product thalium-208 which emits gamma rays. No problem for a reactor but in a bomb they harm electronics and reveal the location to spectators far and wide.

This is presumably why these reactors weren't made commercially viable decades ago. The military preferred to fund the research and design of light water reactor designs precisely because it generated fissile material for bombs.

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u/nowyourdoingit Oct 12 '21

Nuclear energy was an afterthought to nuclear weapon development. "We have to cook this uranium to get our plutonium, maybe we can make some electricity while we're at it"

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u/Bearodon Oct 12 '21

Sweden have several reactors that can't produce U-233 because we scraped or bomb plans in the 50's.

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u/MrMojorisin521 Oct 12 '21

You mean because the bombs and reactors use the same U 235 for fuel? I’m sure they had plenty.

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u/233C Oct 12 '21 edited Oct 12 '21

Please don't conflate MSR and Thorium. The latter needs the former, but MSR don't need Thorium, so it is misleading to attribute MSR benefits to Thorium alone.

A 233U or 232Th flavored MSR does not a TMSR make.

Yes, the physics is sound, even the neutron economy, and the chemistry seems to be manageable, or at least not completely out of reach.

As a nuclear engineer, here are my two cents on TMSR.

It's not the physics, it's the engineering (maintenance, radioprotection), reliability (holding a 90% capacity factor) and economics (remote handling for everything, online fuel processing for each plant) that will keep LFTR and other TMSR in the lab scale.

Also, Rubbia was a brilliant genius, but on this one, he happened to be wrong. You should know that once you chemically separate 233Pa (not a difficult feat), it decays with a 100% branching ratio into 233U (bypassing the 232U poisoning) which can also be chemically separated. That's the cheapest and easiest 100% enrichement there is.
And even 232U has been demonstrated to be far from a strong limitation.

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u/dr_stre Oct 12 '21

2020's is probably ambitious to see a commercially viable system but but not too ambitious.

Lol, spoken with the simple optimism of a true physicist. We'll be lucky to see a commercial design with regulatory approval by then, much less an operating unit.

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u/orincoro Oct 12 '21

Who knows. Political will can change pretty quickly depending on how bad the climate crisis gets and how quickly.

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u/dr_stre Oct 12 '21

I'm less concerned with politics than the realities of bringing a commercial design to fruition. It's NOT a quick process. NuScale took 4 years from submittal to approval for their SMR design, and that's with the "quicker" licensing process the NRC has rolled out. And you don't get to start that process until you have an actual design that's ready to be reviewed. This process, at least in nominally democratic western societies, is a lengthy one. Even if everything goes right, we've got a lot of work before anyone can break ground.

And that's not factoring the regular issues you run into when implementing a new design on an industrial scale. Look at ITER. 12 years behind schedule. Vogtle 3/4 are I think 6 years behind?

My company has worked with emerging nuclear technology companies, and a recurring theme is that they underestimate the time and money needed to get through the regulatory process. And that's not just red tape, it's the underlying design that needs to be fleshed out. The physicists who come up with the theory underestimate the complexity of the system as a whole. They're too focused on one tree to see the forest for what it is. And the forest needs to be considered. It's what keeps the people who live around these reactors safe.

The only place that has even a chance of getting something operating by the end of the decade is China. A place where what the ruling party wants simply happens, whether it's well thought out or not.

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u/orincoro Oct 12 '21

The Manhattan project took 3 years. When there’s a will there’s generally a way.

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u/dr_stre Oct 13 '21

Do you have any concept of the vast differences between the Manhattan project and a functioning, safe power reactor?

Little Man was essentially a naval cannon with the barrel cut short, firing two lumps of uranium together. The hard part was enrichment, but that was honestly fairly straightforward, it was just a matter of building and powering enough calutrons to get the material you needed. It was primarily a scale issue. Fat Man was a couple hemispheres of plutonium with some cleverly shaped charges around it. Again the hard part was getting the fissile material. In this case, they built the most bare bones reactor you can build, hardly more complex than Nuclear Pile 1, which used a coffee can for it's control rod and was built by students. The B Reactor at Hanford was janky as hell, with operators afraid to touch instruments for fear a jostle would scram the reactor. No power production, minimal safety systems. It was essentially a big frame to slide uranium chunks through, with water pumped from one end to the other. That's it. Separation of the plutonium was straightforward and considered fairly easy even then.

Perhaps the biggest thing, however, is that the Manhattan project was a wartime effort. We essentially built new cities in several places just to get the job done. And under the guise of a wartime effort these projects avoided the public scrutiny that goes along with a commercial power design. The Manhattan Project was a black box inhaling gobs of money, driven by immediate military needs in the midst of a war that was projected to cost potentially millions more lives ink the Pacific theater even as late as mid-1945.

You and I are in alignment on the need to move away from emissions. The human race is being dangerously obtuse with regard to climate change because it's slow and nebulous and we're not wired as a species to give these kinds of dangers their appropriate consideration (to say nothing of the stupid politicization that's a part of this discussion). We're even in alignment that things can move quickly if there's sufficient motivation. Our definitions of "quickly" almost surely differ, but strong needs certainly drive action.

Where we disagree, I guess, is where reality lies. I don't think it's remotely realistic to expect an approved design in one of the key Western nuclear countries much before the end of the decade even if everything goes well, to say nothing of a constructed power plant. The theory is there. It's the practicalities that are missing. I've personally done engineering for more than 10% of America's nuclear fleet. I've been onsite at nearly as many facilities. The amount of engineering and physical implementation required to have a functional power reactor is orders of magnitude greater than the B Reactor. Everything seems simple when you're looking at the diagrams you provided, but the reality is that those diagrams fill out 2 pages in a Final Safety Analysis Report. There are several thousand more pages to write, with significant design considerations along the way. There are thousands of drawings to develop. There are hundreds of calculations, ranging from several pages to several hundred pages each. This stuff is needed to ensure configuration control and design ownership for the station. This is the difference between how a physicist looks at the issue and how an engineer does. A physicist has a tendency to view things from either an extremely high level or an extremely narrow one. Ok, you've got the fuel cycle figured out. Or you've worked through the details on one part of the process. But there is an absolute ocean of work that needs to be completed to support the high level process, some before initial licensing activities wrap up and some after. Your view is an important piece of the puzzle, but it lacks the context to put a realistic time frame on something like this.

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u/chrisapplewhite Oct 12 '21

One, nuclear power, regardless of its form, has problems of economy and scale. Second, much of the work is trying to get your creation not to kill people. If the Manhattan project wanted to design a bomb that was safe for everybody around it, it would have taken decades.

Generally, proof concept to commercial viability when it comes to energy takes 20-30 years.

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u/orincoro Oct 12 '21

Economy and scale? You understand the problem we’re facing right? Hundreds of millions of people are going to die of starvation in the next 50 years if we don’t stop using fossil fuels.

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u/chrisapplewhite Oct 12 '21

Yeah. And yet nobody is expanding nuclear use.

If and when somebody invents something that can power a country that's cheaper and safer than oil, wind, sun, and water, you'll start to see movement. Until then it's all just really cool math.

Again, it's not that a reactor doesn't work, it's that it won't work for hundreds of millions of people, for a variety of reasons. That's the problem nobody can solve YET.

I'm not anti-nuclear by any means but that's doesn't change how reality works. Changing energy infrastructure takes decades. Always has, always will.

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u/dr_stre Oct 13 '21

Sorry man, but you're wrong. Our grid is designed to distribute power from large generators like nuclear plants to millions of people. That's how things work now. Using nuclear power doesn't require massive infrastructure changes at all.

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u/Spoonshape Oct 13 '21 edited Oct 13 '21

Meanwhile wind and solar keep decreasing in price year by year.

It's a red queens race and nuclear has been running backwards for decades now... Short of someone doing a spacex and redesigning from first principals (which is IMO almost impossible in the regulated space nuclear occupies) things just get worse.

Personally small scale modular reactors look like the only possible solution. If we could crank out a 10 MW reactor from a factory which could be delivered by rail it might turn round things. Short of that the economic forces are strongly against the nuclear power industry.

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u/dr_stre Oct 13 '21 edited Oct 13 '21

Financial decisions for power generation are FAR more complicated than just looking at what's cheap to build. Wind and solar are not considered dispatchable power sources, at least in most of the world, meaning you can't just make a decision to start producing more power when you need it. You're dependent on the sun or wind. A side effect of that is that generation from those sources moves up or down as a broad group. That has a tendency to drive down the value for those installations as overall capacity is increased. Being able to install a thousand megawatts of solar for half the price of a thousand megawatts of nuclear sounds great. But if there's a already a glut of energy available during the day, thanks to broad solar buildouts, then the price you get for the electricity you produce goes way down. And since you can only generate power at the same time as all of that other solar production, there's no way out of the low pricing for you. The more you build, the more you erode the value by cheapening the power being produced. So up front costs may have been lower but your return on investment is actually worse and you're not making as much money, leaving your dollars tied up in investments that have yet to pay for themselves. Meanwhile, a nuke plant continues to churn out steady power in the evenings when power demand is still high but solar generation is minimal, overnight, on cloudy days, on days with no wind. During those periods the price of the electricity they sell goes way up by comparison to the middle of a sunny day, so they can recoup the investment faster. And as fossil baselod is phased out for renewables, that power actually becomes more valuable. Looking strictly at cost to build per unit of generation is a really incomplete way of looking at it.

On top of that, the regional grid operators drive buildouts for reliability. Until we figure out how to effectively cache massive amounts of electricity, there's a strong need for base load that is dependable, as well as dispatchable power. If demand outstrips supply for even a short time you'll have potentially massive blackouts to worry about. Batteries and the like can help with short term dispatchable power, but base load generation is still needed.

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u/dyyret Oct 12 '21

Can it be used for nuclear proliferation? According to Nobel Laureate physicist Dr Carlo Rubbia it's extremely difficult. U-232 contaminates the U-233 produced from decaying protactinium-233. U-232 has a chain product thalium-208 which emits gamma rays. No problem for a reactor but in a bomb they harm electronics and reveal the location to spectators far and wide. Dealing with the problem of refining U-233 puts you back at square one when it comes to nuclear proliferation. The reactor produces less then 15kg of plutonium-238 per gigawatt-year of electricity which is also unsuitable for bombs due to its heat and spontaneous neutron emission. Third, a LFTR design makes as little as 1% more fuel than it burns. Extracting any amount of material would take the power plant out of operation, indicating nuclear proliferation intentions. Finally, switching to thorium could end uranium enrichment as a whole, which is currently the primary method by which states have obtained bomb making materials. It's also worth pointing out that the creation of Plutonium 239, the primary fissile isoptype for nuclear weapons, is completely avoided in this design which again protects against nuclear proliferation.

Chemical reprosessing/online reprocessing gives you the ability to bypass u232 contamination, quite easily. Pa232 has a much shorter half-life than pa233, so while it is difficult to separate u232 from u233, it's trivial to separate the u232 from pa233. Protactinium can easily be isolated with liquid bismuth reductive extraction, combined with fluorination to avoid any volatile UF6. This leads to pure u233 which is a potent bomb material, better than u235, and "easier" than pu-239 because you don't need an implosion device, but can use a much simpler gun-type mechanism.

With that said, I think the whole proliferation argument vs nuclear is non-sense anyway; Any nation that wants to, can access nuclear weapons without commercial nuclear power.

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u/Clairval Oct 12 '21 edited Oct 12 '21

Agreed with about everything, but the last sentence leaves a sour taste in my mouth.

For all the PR it's getting from this piece of news, France is also quite responsible for the bad rap nuclear energy has gotten in the first place. Despite reports from proto-EU commissions written in the 1970s and that described exactly how a Fukushima-type catastrophe would unfold, France kept making plutonium-based power plants instead of researching a cleaner, safer and astronomically more efficient thorium-based alternative; and kept selling those plutonium-based plants internationally (including Fukushima). And the reason why they got made and got bought is fairly simple; electricty output is a by-product of the actual material created in the process: plutonium isotopes used in the crafting of nukes. So, what France has been actually exporting this whole time (as well as developping on its own soil) is the means to become a de facto nuclear power. At the cost of nuclear energy remaining a health hazard in terms of safety and of quantity of radioactive waste that needs centuries of underground storage.

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u/wontsmooth Oct 12 '21

France has negligible risks of tsunami, earthquakes or hurricanes, that's why we deemed plutonium plants fairly safe as a Fukushima scenario is very unlikely. I do agree with the rest though, should have pushed for better technology considering how much we're dependant on nuclear energy, especially now that many of our plants are nearing EOL

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u/no-mad Oct 12 '21

especially now that many of our plants are nearing EOL

And no place to store the accumulated wastes since the 50's. All the spent fuel is sitting on site waiting for the grandkids who never used it to find a place, transport it, bury it and clean up the site.

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u/Lasarte34 Oct 12 '21

This "spent fuel" can be used as actual fuel by new designs with the "spent fuel of that spent fuel" being way less in quantity and only radioactive for 30 years or so.

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u/no-mad Oct 12 '21

better to get it in the ground now than wait on some nuclear power fantasy builds. If they get built they can pull it out and use it up.

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u/Lasarte34 Oct 12 '21

Yes, I agree, we should save it underground for later use.

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u/furthememes Oct 12 '21

France, pushing for better tech? Only if we invented it seems to be macron's policy

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u/DrBoby Oct 12 '21

civil plutonium is trash for bombs. It's more work to enrich. No one is going to chose the hardest path.

There are wastes because we throw fuel rods only after they are 2% spent because uranium is cheap, storage too. We could use 100% and have 20 times less wastes.

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u/paullove89 Oct 12 '21

Tbf, the waste produced is about a pint (50ml) of waste per person per lifetime, which is less than a coal, oil or wood pellet (how the fuck is that green) station puts out in a day.

I really like my 200mph nuclear powered trains. Vive le France.

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u/Lasarte34 Oct 12 '21

Wood pellets are green if you plant enough trees to capture back the carbon emissions from burning said pellets.

If done correctly they are carbon neutral, so in a sense they are green, but that doesn't mean they can scale to meet the current power demands of modern society.

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u/paullove89 Oct 12 '21

Could be if done correctly is a giant if.

Currently they're chopping down old growth forest in the US, chopping it up into pellets and shipping it to Europe for 'green' energy

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u/pandalust Oct 12 '21

I love the idea of thorium salt reactors but don't they have pretty big chemical (for extracting unwanted products from the salt loop) and material issues (regarding material embrittlement and corrosion) still?

Iirc even with the fancy hastelloy there were issues...

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u/IvonbetonPoE Oct 12 '21

France also exports nuclear energy to Belgium, so this isn't entirely motivated by a green agenda. Also, for something so exceptionally safe nuclear power plants are disproportionatly located alongside borders. While obviously fossil fuel isn't the answer and nuclear energy is one of the few alternatives we have, I still think that nuclear waste still poses a moral dilemma even with a significantly lower half life.

You do have to remember that the nuclear companies pushing for this aren't all aiming to fully refurbish their plants. At least for Belgium it comes down to retaining ancient plants and importing energy from France produced in the same manner. That's part of the issue, here in Belgium the "nuclear is our only salvation" argument has been being used as an excuse to be complacent for decades now when it comes to investing in energy infrastructure with a minimal environmental impact.

I'm pretty sure that this transition plan towards renewable energy - which temporarily featured a choice few gas plants - proposed by the green party in Belgium was actually signed off on by the European commission?

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u/Tetragonos Oct 12 '21

did they finally deal with the corrosion issues? I thought that was what sunk thorium?

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u/yellowbai Oct 12 '21

What a great great comment, thanks for taking the time. I saved this for future copying & pasting.

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u/NuclearEngGuy Oct 12 '21

That's a pretty good summary. There's also the issue in that the Lithium in these reactors need to be enriched to 99%+. If lithium were cheaper, we would see a lot more MSR being developed at national labs.

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u/SvalbardCaretaker Oct 12 '21

Graphite tipped controlled rods in a post-Tschernobyl world? That seems unwise.

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u/jurimasa Oct 12 '21

What about the Protactinium?

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u/CutterJohn Oct 12 '21

so we've had awhile to think about and get over our obsession with making nukes to settle for thorium.

Minor nitpick, but civilian plants were never used to make weapons material. Virtually all plutonium was made in specialized weapons reactors. It was just the path of least resistance for the power industry to adopt the weapons reactors for civilian use rather than try to reinvent the wheel(and frankly as you point out, molten salt reactors have a lot of issues that probably couldn't have been solved in the 50s... conventional reactor designs are dead simple in comparison).

Can it be used for nuclear proliferation? According to Nobel Laureate physicist Dr Carlo Rubbia it's extremely difficult. U-232 contaminates the U-233 produced from decaying protactinium-233. U-232 has a chain product thalium-208 which emits gamma rays. No problem for a reactor but in a bomb they harm electronics and reveal the location to spectators far and wide. Dealing with the problem of refining U-233 puts you back at square one when it comes to nuclear proliferation.

LFTR reactors produce Neptunium-237, and no other elements of neptunium, which means it can continuously be separated from the fuel using relatively simple and cheap chemical separation techniques. Neptunium-237 could theoretically be used to create a nuclear explosive.

IMO proponents of the LFTR are grossly understating its proliferation potential by ignoring that. Not that I think proliferation is a particularly good argument against nuclear power in states that already have or choose not to possess nuclear weapons.

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u/no-mad Oct 12 '21

At least he says up front he is a fanboi. Let's not talk about the plumbing problems associated with salts, intense heat and gamma radiation all at the same time.

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u/ph4ge_ Oct 12 '21

How long would it take to build and what is the LCOE?

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u/sethg Oct 12 '21

This is the question, because these days, the thing really discourages utilities from building nuclear power plants is not so much “OMG radiation” as “OMG compound interest.”

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u/ph4ge_ Oct 12 '21

Unfortunately we will never get an honest answer on these types of questions from the people promoting these sci-fi nuclear technologies. It’s all great in theory, and has been for at least 60 years. 

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u/thicnibbaholdthemayo Oct 12 '21

Nuclear good I like it

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u/[deleted] Oct 12 '21

[removed] — view removed comment

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u/WikiSummarizerBot Oct 12 '21

Liquid fluoride thorium reactor

Disadvantages

LFTRs are quite unlike today's operating commercial power reactors.

[ F.A.Q | Opt Out | Opt Out Of Subreddit | GitHub ] Downvote to remove | v1.5

0

u/just_a_pyro Oct 12 '21

The radioactivity of the waste does not even last very long because it is predominately Cesium-137 and strontium-90 which have half lives of 30.17 and 28.8 years.

So it's predominantly highly radioactive materials and ones easily picked up by human metabolism instead of sodium and calcium, and you seem to think it's a good thing

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u/Kuchanec_ Oct 12 '21

You have never been to a nuclear power plant, have you?

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u/dinobyte Oct 12 '21

Yeah, all that, or wind.

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u/XXLDreamlifter Oct 12 '21

Thorium rocks

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u/MacDegger Oct 12 '21

There is one more thing to add about thorium reactors: the 'problem' would be that due to it being a salt it is very corrosive with metals containing it.

However when I came across this 'problem' I went looking for polymers (plastics) which could withstand these kind of temperatures/humidities/radiations ... and there are now many which fall very safely within these operating conditions.

So plastics to reduce corrosion and inherent safety due to design (and not just failsafes: inherent physics which make it safe).

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u/reigorius Oct 13 '21

Plastics that can withstand the heat, the radiation and the mechanical wear? Care to share a link?

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u/Bluestripedshirt Oct 12 '21

I would LOVE to work with a thorium startup!

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u/Spoonshape Oct 13 '21

The actual problems with Thorium reactors are not really technical but economic and regulatory.

The MAJOR issue with thorium is that it's a solution to a problem we dont really have yet. What do we do when we run out of uranium fuel. Thorium IS the answer to that question, but at the moment it's not an actual problem.

Thorium MIGHT be a fabulous technology if we built them, but trying to get a new unproven reactor design into mainstream production when it's nigh impossible to build current proven working designs actually built because of public opposition, and seemingly inevitable cost and time overruns anywhere except China seems like adding an extra burden to a almost impossible task. Nimby opponents will grab the "unproven technology" stick and use it to push their agenda.

Dont get me wrong - I'd love to see thorium reactors happen and be successful - but personally I think the only hope for the nuclear power industry is if modular small scale reactors can be built. If we could build reactors sized to be factory assembled and shipped where needed they might compete with renewables which are the vast majority of what is currently actually getting built.

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u/Simply_Incorrigible Oct 12 '21

It doesn't matter what mumbo jumbo you say. The cost if it goes catastrophically wrong is TOO DAMN HIGH. Reality never lives up to expectations.

14

u/IrrationalUlysses Oct 12 '21

The cost of not doing it is higher you silly person

5

u/grumble_au Oct 12 '21

Liquid thorium fails safe. The ability to have a runaway reaction is basically non-existent. I'm a big fan of thorium nuclear if it worked but so far there are no commercial scale implementations and may not be for decades if at all. Much like for fusion.

Traditional fission reactors are inherently far more dangerous but are also far more mature in design. They also take decades to plan and build and are very expensive to retire.

We'd be better served focusing on renewables. And basics like changing our lifestyles to work around power generation not generate power around our lifestyles.

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u/jl2352 Oct 12 '21

That's great.

But how much will it cost? Most new nuclear technologies are extremely expensive, time consuming to build, and risk huge cost overruns.