The facts are not nearly as good as the current group think on/. would have you believe.
First the basics. Th is not a fuel but is fertile. That is you can turn it into fuel with neutrons, which you can get from your final fuel. Chicken egg issues are solved with a 235U or Pt starter. 232Th is transmutation into 233Pa which is a neutron poison. The breading ratio is already marginal so you need to constantly remove this for any hope of a useful breading ratio (ie you make at least as much fuel as you burn). The 233Pa decays into 233U. That is right the fuel is still Uranium. Its a lighter isotope and tends to fission better and produce less actinides. Actinides are things higher up the periodic table than Uranium and are the hard stuff to deal with in nuclear waste. Less is not none. But then you don't have any 238U sitting around producing Actinides either. So that is good.
So lets start with some basics issues. We have to get the 233Pa out continuously... We are still burning Uranium and as such the fission product waste is the same, the decay heat(ie shut down is not the same as won't melt down) is the same, the radioactivity of the core is the same. So we still have about the same waste as any other Uranium reactor with reprocessing and we have the same core breach/meltdown issues as any other reactor. Proponents compare it too a once though Uranium cycle and claim 50x less waste or whatever. Lets be clear, once through fuel cycles are braindead.
So why the claims of "solves all issues with nuclear energy"? It is how the first issue was solved. One way to get the 233Pa out continuously before it becomes 234Pa is to use liquid fluoride salt. In fact any salt will do but fluoride has only one isotope and some favorable chemistry and physical properties. It should be noted we are dissolving 233U in this salt and as such 238U and 235U is equally soluble. Now the fuel is part of the primary coolant. This is one example of a larger class of homogenous reactors and have many nice properties regarding control and off design point behavior, even burn etc. None of these advantages have anything to do with Th. Basically burning actinides in this class of reactor is fairly easy compared to where the fuel is solid. That is we can burn plain old 235U/238U in a fast configuration with all the same waste advantages and safety advantages as proponents claim for Th.
But this is not the whole story. No matter what you do you always get a little 234U (from 234Pa and 233U that does not fission). This is a hard gamma emitter and its claimed because glove in box type procedures cannot be used this makes building bombs much harder. This is true. But we *must* handle this to reprocess. If you can handle these hard gammas for reprocessing you can handle them for bombs. In fact they did. 233U bread from Th was used at least partially for one (even 2) bomb tests. Also you can always just put 238U around the reactor to get plain old 239Pt for the old fashion type bomb. Any reactor is always something of a proliferation risk. Also how much extra will dealing with these gammas cost?
Finally lets consider some real world experience. It was claimed that pebble bed reactors where passively safe and nothing could go wrong. Well the prototype in Germany was a total disaster. Between leaks of radioactive material, blocked pipes and all sorts of issues with the fuel elements. Now its a decommissioning nightmare. So much for safe. This is the same. Just because you claim something can't happen, does not mean it can't. Next consider that there has never been a breading Th reactor. A breading ratio of 1 has not been demonstrated.
TL;DR: Most advantages are because its a molten salt reactor with in situ reprocessing. Most of these advantages applies to Uranium fuel cycles as well. Waste stream is the same as Uranium used in similar reactors. Its still a nuke plant. With no real instant shutdown (decay heat) and all the same issues with a core breach or melt down as any other nuclear plant. They are not a silver bullet.
At 512 bits far a hash we need on average 2^256 hashes to find a collision using the birthday paradox/trick. Lets assume you have 100,000 cores each that can do 4 billion hash per sec (far faster than we can do right now). It will billions of trillions of zillions of gazillions of times longer than the current age of the universe to find this hash collision. Never mind that there are not enough fundamental particles in the universe for the required storage. Even at a hash per particle.
Hashes should be fast. If you want it to be slower, rehash a million times.
I never said we did [need to give up western lifestyles]. But a lot of people seem to think it will happen [AGW fix] when everyone else... like say china gets their act together. Rather than us.
I don't have a car.. which is really nice when you live in a place where you really don't need it. I elect to use trains even with the higher time costs than planes whenever I can (Europe to NZ in a train is a little bit difficult). I restrict my long range flying as much as possible in my job. I don't heat much in the winters and have top of the line windows etc.... But will you pay $5 a kWh for electricity? Or 10USD for a gallon of gas, or support the local government when they switch from landfill to recycling along with the large increase in local rates/tax? What about some *serious* R&D money in the next Budget? That is where we don't really support a change.
Please tell me your joking right? You seriously think one party out of 2 is going to better than the other? Governments see one thing with AGW comes up... new tax revenue opportunities. And that has nothing to do with real solutions.
Pro tip with real stuff... its not summed up with 2 view partisan politics.
Hipsters? Where did i say that? Fact is even the "believers" as you call them/us are not really doing anything useful. And when it comes down to things that may in fact work, no one wants it. We all still want cheap electricity, computers, cars, water, food, cloths etc. People are *not* holding back from spending interesting amounts on things like smartphone and the like, while at the same time complaining about China's CO2 output........
The problem has never been the disbelievers.... Its always the hypocrites.
Not just the most anticipated... the most anticipated smartphone in history! Of course smartphone history is what, something like 6-10 years depending how you slice it? Most anticipated phone in a decade? meh, that just doesn't have the right ring to it.
That is the problem. Everyone wants *everyone else* to deal with. As long as they can still drive to work with cheap gas and get a shiny new smart phone every year, its clearly other peoples real problem... if only they would deal with it right?
Of course the reason they needed a clever hack in the first place was because the engineers had used different shaped CO2 scrubbers for the lander and the command module. Engineering at its finest. Not.
One, there is almost no He3 on the moon, sure the ratio compared to He4 is massive... but that is not the same thing as a decent amount of He3. Its about 50ppb or less, the average is more like 1ppb. You would use more energy mining it that you get from the He3. Note this more than 1000 times more dilute that commercial quantities of Uranium.
The second big problem is that He3 fusion is ~50 times harder to do than DT fusion which we can't do! So even if you get some He3, you can't burn it. If we can do He3 fusion we can also do plain old DD fusion and save the trip to the mine on the moon.
Lets run a number or 2. The US uses just a little more than 3900 TWh of electrical energy per year. That is 14x10^21 J. Quite a bit. 1 mole (3g) of He3 fused gives us 614GJ . Se we need 7622kg of He3 per year at 100% efficiency. Now is that 50ppb by weight or not? i don't know and i will assume by weight (this is more conservative). The average is closer to 1ppb but lets see what we get at 50ppb. Assuming 100% extraction (totally unrealistic) we need to mine 153x10^9 kg per year. At 1ppb its 50x that, or more like 7650x10^9 kg (7600 million tons)! The he3 is only in the top layer. At 1 meter deep, that is an area of 50x10^6 meters, or a square about 7km on each side. With closer to true average levels of 1ppb (some papers even claim as low as.1ppb) its a square 50km a side. For just one year just for the US, on the moon!
We won't do it. We will just use DD fusion where the fuel is readily available from water right here...
Unfortunately at 50ppb or less you will use more energy mining that you get out of it. That is assuming you have He3 fusion working which is many times harder than DT fusion which we still *don't* have.
Most Europeans travel well outside Europe. For example, USA is a popular destination as is Canada. Of course so is the rest of the world. In fact out of the 20 people working with me, every single one as traveled 5000 miles or more at least once (mostly to the US). I guess i could dig up real stats.. but meh.. it doesn't really matter.
You seriously think the monkeys at TSA can keep a plane bomb free? The reason they are bomb free is that no one brings on bombs. The few that have tried, succeeded. First time.
You can't defend the safety of nuclear power by claiming all the accidents are due to corruption and negligence. Fact is we now know that some plants are susceptible and are not as safe as some say because of corruption and negligence.
Plus, focusing just on large hydro is probably distorting, since one tends to use up large-hydro opportunities first and then move down to smaller hydro.
How is this different from pump storage. Where the first ones get the best and cheapest sites, but later ones get more expensive because they need to be built in less optimal ones. Also you need more that a mountain, you need water, so the worst sites are going to need lakes for both sides doubling impact and probably cost.
*we already have cost figures for pumped hydro*
No we don't, we have figures for existing ones that got the best and cheapest sites. Tell me what the cost of *500* more in Europe? It is totally unrealistic for a real solution. Its only nice if all you want to do is talk about how easy it would be... Which is *not* a practical engineering solution.
Slashdot Mirror
The facts are not nearly as good as the current group think on /. would have you believe.
First the basics. Th is not a fuel but is fertile. That is you can turn it into fuel with neutrons, which you can get from your final fuel. Chicken egg issues are solved with a 235U or Pt starter. 232Th is transmutation into 233Pa which is a neutron poison. The breading ratio is already marginal so you need to constantly remove this for any hope of a useful breading ratio (ie you make at least as much fuel as you burn). The 233Pa decays into 233U. That is right the fuel is still Uranium. Its a lighter isotope and tends to fission better and produce less actinides. Actinides are things higher up the periodic table than Uranium and are the hard stuff to deal with in nuclear waste. Less is not none. But then you don't have any 238U sitting around producing Actinides either. So that is good.
So lets start with some basics issues. We have to get the 233Pa out continuously... We are still burning Uranium and as such the fission product waste is the same, the decay heat(ie shut down is not the same as won't melt down) is the same, the radioactivity of the core is the same. So we still have about the same waste as any other Uranium reactor with reprocessing and we have the same core breach/meltdown issues as any other reactor. Proponents compare it too a once though Uranium cycle and claim 50x less waste or whatever. Lets be clear, once through fuel cycles are braindead.
So why the claims of "solves all issues with nuclear energy"? It is how the first issue was solved. One way to get the 233Pa out continuously before it becomes 234Pa is to use liquid fluoride salt. In fact any salt will do but fluoride has only one isotope and some favorable chemistry and physical properties. It should be noted we are dissolving 233U in this salt and as such 238U and 235U is equally soluble. Now the fuel is part of the primary coolant. This is one example of a larger class of homogenous reactors and have many nice properties regarding control and off design point behavior, even burn etc. None of these advantages have anything to do with Th. Basically burning actinides in this class of reactor is fairly easy compared to where the fuel is solid. That is we can burn plain old 235U/238U in a fast configuration with all the same waste advantages and safety advantages as proponents claim for Th.
But this is not the whole story. No matter what you do you always get a little 234U (from 234Pa and 233U that does not fission). This is a hard gamma emitter and its claimed because glove in box type procedures cannot be used this makes building bombs much harder. This is true. But we *must* handle this to reprocess. If you can handle these hard gammas for reprocessing you can handle them for bombs. In fact they did. 233U bread from Th was used at least partially for one (even 2) bomb tests. Also you can always just put 238U around the reactor to get plain old 239Pt for the old fashion type bomb. Any reactor is always something of a proliferation risk. Also how much extra will dealing with these gammas cost?
Finally lets consider some real world experience. It was claimed that pebble bed reactors where passively safe and nothing could go wrong. Well the prototype in Germany was a total disaster. Between leaks of radioactive material, blocked pipes and all sorts of issues with the fuel elements. Now its a decommissioning nightmare. So much for safe. This is the same. Just because you claim something can't happen, does not mean it can't. Next consider that there has never been a breading Th reactor. A breading ratio of 1 has not been demonstrated.
TL;DR: Most advantages are because its a molten salt reactor with in situ reprocessing. Most of these advantages applies to Uranium fuel cycles as well. Waste stream is the same as Uranium used in similar reactors. Its still a nuke plant. With no real instant shutdown (decay heat) and all the same issues with a core breach or melt down as any other nuclear plant. They are not a silver bullet.
Question: Why is there more than 7000000000 people on earth?
Answer: We are not as good at killing each other as our own dogma would have us believe.
There are companies that are older than 200 years you know.
200 years is not a few years. Most of the activity is from things with half lives well below a century. Assume you reprocess and burn Actinides.
At 512 bits far a hash we need on average 2^256 hashes to find a collision using the birthday paradox/trick. Lets assume you have 100,000 cores each that can do 4 billion hash per sec (far faster than we can do right now). It will billions of trillions of zillions of gazillions of times longer than the current age of the universe to find this hash collision. Never mind that there are not enough fundamental particles in the universe for the required storage. Even at a hash per particle.
Hashes should be fast. If you want it to be slower, rehash a million times.
I never said we did [need to give up western lifestyles]. But a lot of people seem to think it will happen [AGW fix] when everyone else... like say china gets their act together. Rather than us.
To claim its not us, but some nebulous few uber rich provably wrong. We are the rich when it comes to CO2 footprint.
So tell which dumbass is different again?
I don't have a car.. which is really nice when you live in a place where you really don't need it. I elect to use trains even with the higher time costs than planes whenever I can (Europe to NZ in a train is a little bit difficult). I restrict my long range flying as much as possible in my job. I don't heat much in the winters and have top of the line windows etc.... But will you pay $5 a kWh for electricity? Or 10USD for a gallon of gas, or support the local government when they switch from landfill to recycling along with the large increase in local rates/tax? What about some *serious* R&D money in the next Budget? That is where we don't really support a change.
Says the guy with a computer in the "western" world with a lifestyle that supports browsing the web and commenting on posts when is so suits.
News flash.. you are that minority. (And so am I of course.)
Please tell me your joking right? You seriously think one party out of 2 is going to better than the other? Governments see one thing with AGW comes up... new tax revenue opportunities. And that has nothing to do with real solutions.
Pro tip with real stuff... its not summed up with 2 view partisan politics.
Hipsters? Where did i say that? Fact is even the "believers" as you call them/us are not really doing anything useful. And when it comes down to things that may in fact work, no one wants it. We all still want cheap electricity, computers, cars, water, food, cloths etc. People are *not* holding back from spending interesting amounts on things like smartphone and the like, while at the same time complaining about China's CO2 output........
The problem has never been the disbelievers.... Its always the hypocrites.
Not just the most anticipated... the most anticipated smartphone in history! Of course smartphone history is what, something like 6-10 years depending how you slice it? Most anticipated phone in a decade? meh, that just doesn't have the right ring to it.
Thing is, we didn't live sustainably in the 1700s either....
You first.
That is the problem. Everyone wants *everyone else* to deal with. As long as they can still drive to work with cheap gas and get a shiny new smart phone every year, its clearly other peoples real problem... if only they would deal with it right?
So what are you doing to deal with it?
Of course the reason they needed a clever hack in the first place was because the engineers had used different shaped CO2 scrubbers for the lander and the command module. Engineering at its finest. Not.
Why do we need machine learning? Surly we can tell them what to do remotely. Robots does not mean removing humans from the loop.
Yea but nobody is dead... Wonder how much of all this hardware that is going wrong it just there to keep the meat bags alive?
Only 2 really big problems with that idea.
.1ppb) its a square 50km a side. For just one year just for the US, on the moon!
One, there is almost no He3 on the moon, sure the ratio compared to He4 is massive... but that is not the same thing as a decent amount of He3. Its about 50ppb or less, the average is more like 1ppb. You would use more energy mining it that you get from the He3. Note this more than 1000 times more dilute that commercial quantities of Uranium.
The second big problem is that He3 fusion is ~50 times harder to do than DT fusion which we can't do! So even if you get some He3, you can't burn it. If we can do He3 fusion we can also do plain old DD fusion and save the trip to the mine on the moon.
Lets run a number or 2. The US uses just a little more than 3900 TWh of electrical energy per year. That is 14x10^21 J. Quite a bit. 1 mole (3g) of He3 fused gives us 614GJ . Se we need 7622kg of He3 per year at 100% efficiency. Now is that 50ppb by weight or not? i don't know and i will assume by weight (this is more conservative). The average is closer to 1ppb but lets see what we get at 50ppb. Assuming 100% extraction (totally unrealistic) we need to mine 153x10^9 kg per year. At 1ppb its 50x that, or more like 7650x10^9 kg (7600 million tons)! The he3 is only in the top layer. At 1 meter deep, that is an area of 50x10^6 meters, or a square about 7km on each side. With closer to true average levels of 1ppb (some papers even claim as low as
We won't do it. We will just use DD fusion where the fuel is readily available from water right here...
Unfortunately at 50ppb or less you will use more energy mining that you get out of it. That is assuming you have He3 fusion working which is many times harder than DT fusion which we still *don't* have.
Most Europeans travel well outside Europe. For example, USA is a popular destination as is Canada. Of course so is the rest of the world. In fact out of the 20 people working with me, every single one as traveled 5000 miles or more at least once (mostly to the US). I guess i could dig up real stats.. but meh.. it doesn't really matter.
You seriously think the monkeys at TSA can keep a plane bomb free? The reason they are bomb free is that no one brings on bombs. The few that have tried, succeeded. First time.
Find the shiny!
You can't defend the safety of nuclear power by claiming all the accidents are due to corruption and negligence. Fact is we now know that some plants are susceptible and are not as safe as some say because of corruption and negligence.
Plus, focusing just on large hydro is probably distorting, since one tends to use up large-hydro opportunities first and then move down to smaller hydro.
How is this different from pump storage. Where the first ones get the best and cheapest sites, but later ones get more expensive because they need to be built in less optimal ones. Also you need more that a mountain, you need water, so the worst sites are going to need lakes for both sides doubling impact and probably cost.
*we already have cost figures for pumped hydro*
No we don't, we have figures for existing ones that got the best and cheapest sites. Tell me what the cost of *500* more in Europe? It is totally unrealistic for a real solution. Its only nice if all you want to do is talk about how easy it would be... Which is *not* a practical engineering solution.