I got tired of reading godlikeproductions and globalresearch and enenews and the other bullshit sites posting about the Fukushima disaster because they were garbage sources full of fairy tales, improbable conspiracies and Hollywood disaster movie physics. I've not read the item you posted but the link text claims says fuel pellets were blasted thirty kilometres by the force of the explosions. Think about that for a moment, the physics of it, launching ANYTHING that sort of distance requires precision engineering as in large artillery pieces or an explosion that would have levelled the entire site and for kilometres around it too. No giant explosion, site not levelled, no artillery in evidence, bullshit story.
New GenIII reactor designs have a shield/liner that sits between the actual pressure vessel and the core structures that hold the fuel elements and guides for control rods etc. This shield can be removed and replaced during a major refurbishment. It won't stop neutron damage to the vessel but it does cut it down somewhat, extending the reactor's effective life. The GenIII designs are expected to operate within spec for a century absent accident or something unknown appearing in that time (like the Wigner Effect in carbon-moderated reactors) and if nothing much has appeared in the hundreds of LWRs that have operated for forty years and more then it's unlikely something will turn up now.
Even then modern designs like the EPR permit, in theory, the operators to swap out the reactor vessel. GenII designs built the containment structures around the reactor vessel, nowadays it is put in place after most of the nuclear island's concrete has been constructed and it could be removed in a similar manner. It would be a long multiyear undertaking and very expensive so it will probably never happen other than if the vessel fails very early in the reactor's life to justify the cost and effort.
The two Vogtle reactors in Georgia started construction last year as did two new AP1000s Sumner plants in South Carolina, a total of four new starts. The news about the loan guarantees is just that, the loans themselves to pay for construction of the AP1000s had already been agreed. It was expected the guarantees would be issued.
As for long-term investments the US threw an immense amount of taxpayers money into something called the Interstate starting about 80 years ago. How did that work out for you?
I recall reading somewhere that the NRC has a two-year backlog in its approvals process i.e. a power generating company submitting paperwork for a Construction and Operating Licence (COL) today will get it looked at in 2016 at the earliest with a three to five year delay after that for a yes/no decision. The NRC is a US government department hence it's underfunded and woefully understaffed especially in the technical divisions as there are better career opportunities for the qualified engineers needed to go analyse the intensely technical submission documents for a new build.
As for existing plants reaching end-of-life, that's debatable. Usually by the thirty-year mark a plant's non-core units are in train to be replaced, things like steam generators, main pumps etc. Almost all of the current US reactors have upgraded to digital control systems if they were originally built with anaogue controls back in the 1970s. The key irreplaceable parts of a reactor are the reactor vessel and its containment and since they were originally overspecified and overbuilt to an almost ludicrous degree and they have no moving parts in themselves they usually pass inspection with flying colours. It tends to be external factors that will downcheck a reactor -- safety systems, steam generators etc.
If the NRC was to shut down older plants simply because they are old their capacity will be replaced with gas and coal, not nuclear because they're a lot less effort in terms of paperwork and currently they're about as cheap to run assuming no-one cares about the pollution they spew into the atmosphere 24/7.
You could have bought low-dose codeine/ibuprofen or codeine/paracetamol tablets over-the-counter at a pharmacy in the UK. (Reaches into drawer -- Boots own-brand 200mg ibuprofen and 12.8mg codeine tablets, pack of 16 costs about 8 bucks US IIRC, the duty pharamcist would make sure you understood the dosage limits etc. before selling them to you). They would probably done a better job controlling your dental pain than ibuprofen by itself. Anything over 12.8mg of codeine compounded takes a doctor's prescription, usually 30mg (trade name Solpadol) for chronic pain but they are prescribed readily. My landlord gets them for painful gout flareups, for example.
I use the 12.8mg formulation to cope with very occasional migraines, occasionally I raid my landlord's stash of 30mg Solpadol if it's promising to be a bad one. I make sure I don't travel with them to certain countries though as possession of any codeine compound is a criminal offence in some places, like Japan.
I suggested Elon buys a second-hand aircraft carrier and uses that. It would solidify his James-Bond supervillain status and piss off Larry Ellison no end as a bonus.
The continuous-process system envisaged by LFTR enthusiasts needed to purify the molten-salt stream and prevent the reactor from shutting down due to poisoning can be tapped to extract any particular element with a bit of surreptitious work, and that includes extracting pure kickstarter U-235 (which is easy to make a bomb from) or pure kickstarter Pu-239 (trickier to weaponise but still possible) or U-233 bred from thorium (which also works as bomb material but not as well as U-235).
Current conventional reactors produce a mixture of Pu-239 and Pu-240, useless as bomb material, in spent fuel since the operating cycles last for a year or more between refuelling and some of the Pu-239 undergoes another neutron capture to make Pu-240. Pu-239 can't be separated from Pu-240 without great effort; the centrifuges or other enrichment equipment needed could purify U-235 from raw uranium much more easily.
MOX fuel formulations are only a small percentage of Pu, typically something like 6% or so hence the term Mixed-OXide comprising both uranium oxide and plutonium oxide. A MOX fuel element will still have Pu in it after it has spent a cycle in the reactor but much of the original Pu-239 and Pu-240 will have been fissioned. More Pu will have been bred from the U-238 comprising most of the rest of the fuel element but the total inventory of Pu in the spent fuel will have been decreased while producing a significant amount of process heat for electricity generation and other uses such as desalination. The spent fuel rod can of course be reprocessed and the Pu reconstituted as fresh MOX fuel.
I don't know of any proposed LFTR operational cycle that would produce Pu-238 in any significant quantity; breeding up from Th-232 all the way to Pu-238 is a lot of steps requiring several neutron captures and decays with several intermediates which would interrupt the chain if fissioned. Adding Np-238 to the molten-salt fuel might work to make Pu-238 but the only source of Np-238 in quantity is a conventional nuclear reactor...
The LFTR system requires breeding thorium up into U-233 which requires a dense neutron flux, a lot denser than conventional fission reactors. Pu-239 is very good for this but the presence of Pu-240 in the fuel stream degrades that neutron economy as fissioning it produces fewer neutrons than Pu-239. MOX can be burned in existing nuclear reactors with some care to produce useful energy since the U-235 present in the fuel produces a large surplus of neutrons which fissions the Pu-239 and the Pu-240.
If you read the fine article you linked to you will discover the reactor in question at Oak Ridge did not use thorium at all. It only used molten salt with U-233 and later on U-235 as fissile material. Breeding thorium up into something fissile in a molten-salt stream is much trickier with all sorts of problems which at the moment have only been dealt with in Powerpoint slides and a lot of handwaving by LFTR proponents.
As for the impossibility of keeping a Pu purification process secret for long I heartily agree. The folks attempting it only need to do it once and succeed for bad things to happen though. The thought of bomb-grade Pu proliferation happening with other technologies is scary enough that billions of dollars are spent every year around the world covering even less likely eventualities. Adding another point-of-leakage of bomb-grade Pu-239 into the outside world is something to be worried about and an additional expense laid at the door of anyone thinking of building a LFTR.
Pu would only be created in a MSR if it was designed to produce it and/or the fuel mix was preloaded with U-238. The problem with LFTR or any other thorium breeder reactor system is that it needs a kickstarter of fissile material, usually a mixture of U-233 or U-235 and Pu-239 to start the breeding process since Th-232 isn't fissile. The kickstarter for a single 1GWe LFTR would probably have enough Pu-239 in pure form to make several implosion-type weapons.
Folks around the world are burning recycled plutonium in commercial power nuclear reactors today. Not in America, for various reasons (mainly due to a lack of native reprocessing capability and some "not invented here" plus the fact that once-through uranium fuel is incredibly cheap at the moment) but it is being done. It's not bomb-grade material, it's the much safer mixed-oxide (MOX) formulation "contaminated" with Pu-240 which spoils it for possible use in bombs even if it was extracted for that use.
No, proposed thorium breeder reactors like the LFTR breed Th-232 up into fissile U-233 and then fission that to produce energy and enough neutrons to continue the breeding cycle. The kickstarter fuel load with U-235 and Pu-239 initiates the breeding operation (hopefully, it's never been tested for real).
Breeding thorium has been done on a small scale in pebble-bed reactors using a small amount of thorium in the pebbles but relying on most of the fissiel fuel being U-235 to provide sufficient neutron flux to do the breeding which was not sustainable otherwise.
A worry with most of the LFTR designs is that commercial companies will have access to bomb-grade Pu-239 which can be chemically extracted from the kickstarter fuel load. MOX fuel for conventional PWRs has too much Pu-240 in the mix to build functional weapons from.
Ummm, no. The economic factor for Super-Phenix shutting down was that it was an engineering prototype that pushed the envelope a bit too far in various directions. It broke in interesting ways, some due to the liquid sodium coolant, some because of the very intense neutron flux in a very small volume. The fact that the Greens fired a few RPG-7s at it in its early days had little to do with its eventual shutdown. This is La Belle France, remember -- see what they did to the Rainbow Warrior for what they think of Greenpeace.
The folks pushing next-generation breeders such as the assorted LFTRs, travelling-wave and other IFRs and the like have learned from the failures of the early breeder designs but it's likely they will run into other whoopsies themselves as they try to run productively for decades on end at 5 cents/kWh.
President Carter's reprocessing ban was in fact overturned by President Reagan. It costs money, lots of it, to reprocess spent fuel and the money to build commercial reprocessing plants wasn't forthcoming until about fifteen years ago when DoE funding was advanced to build a MOX fuel fabrication plant in South Carolina. The pricetag is now $5 billion, the plant is still unfinished and there are no confirmed customers for its MOX fuel in the US despite, it is claimed, generous subsidies. As far as I know there are no commercial reactors using MOX with recycled plutonium in the US at the moment.
Breeder reactors can't earn their way simply producing plutonium fuel other than for military purposes as cost-no-object operations. They need to generate electricity too and the operational experience of breeders over the past few decades is that they are not reliable and cost-effective to run especially these days when fracked gas-fired power generators can deliver electricity wholesale to the grid for about 3 cents/kWh. The French Super-Phenix breeder was intended to produce 1.2GW of electricity but it suffered problems and delays and was eventually shut down in part due to economic factors. Other breeders have had similar problems over the decades.
As for the START process it can take a decade or more to get something both countries can agree to -- President Obama signed off on the latest START agreement but it was begun by President Bush after the groundwork had been laid in President Clinton's term. The US (and Russia too) have to consider there are other unfriendly nuclear powers in existence today such as China with limited stocks of weapons but with intercontinental range. America's ready-for-use stockpile of about 2,000 deliverable warheads has to be able to deter more than Russia.
The Tohoku coastline on the south-eastern side of Honshu where the Fukushima nuclear plants are located is swept by the Kuroshio current, part of the North Pacific circulatory system dispersing material from the coast across the Pacific. Much of the fallout from the Fukushima disaster has already been thoroughly diluted into the ocean and marker isotopes such as Cs-134 (a fission product with a 2-year half-life therefore very little remaining from US nuclear weapons tests in the Pacific in the 1950s to confuse the results) are starting to be detected at very low levels off the US west coast.
There's still significant levels of radioactivity at and around the Chernobyl site, well above international safety limits for permanent human habitation. Animals tend to have short lives anyway, dying of starvation, disease, predation or accident rather than old age so their chances of developing a lethal cancer (the only real ill effect of mild raised levels of radiation) are low since they die of something else beforehand.
I'd be suspicious of regularly eating food grown in the Chernobyl area unless it was thoroughly tested. If I was to work or live there I'd expect my exposure to radiation to be limited with monitoring and if I took enough exposure over a given period I'd move out.
In the case of Fukushima the evacuated areas around the plant are much smaller and less contaminated than at Chernobyl. There was an illustration I saw once layering the Fukushima release plumes map to scale over the Chernobyl exclusion zone -- the entire area in Japan designated off-limits (less than 1000 square km) was about the size of the marker pinpointing the reactor site on the Ukranian map. Even so large parts of the original Japanese exclusion zone have been reopened to permanent occupation and some of the rest can be visited on a restricted basis while decontamination takes place.
"Google Cherynobyl? To this very day it is so radioactive you can't get within 50 to 100 miles of it?"
After the accident/explosion/fire etc. in 1986 the Ukrainian authorities continued to operate the three other undamaged reactors at Chernobyl (they needed the electricity supplies). After a few years folks started running tourist trips to visit the area including the evacuated towns surrounding the damaged reactor. Thousands of workers have been working on the reactor building for decades attempting to entomb it or at least cover it up so it doesn't leak quite as much residual radioactivity as it does even today.
Sure in a Hollywood disaster movie script the Chernobyl site is so radioactive you can't get within 50 to 100 miles of it. However this is real life which is kinda different.
Ah, I just realised you're trolling, aren't you? Silly me.
I did specify D2O as being 1 part in 40 million, not DHO which is a lot more common. Deuterium for plasma fuel needs to be reasonably pure at the moment, it's one of the things the ITER program is tasked with, to see just how crappy the deuterium:hydrogen ratio in fuel can be and still produce good Q levels and burn times. This will reduce the cost of producing fuel in the long run.
I have a vague recollection the Japanese tokamak you mention (the JT-60?) was running on D-D fuel and they calculated that if they had used D-T they'd have got Q>1 but it wasn't set up to run with tritium. A moral victory if not a real achievement. The Japanese are in the ITER consortium and the JT-60 is being rebuilt and upgraded as part of the total research effort, like JET at Culham.
ITER is being built right now and the designers believe it will give them several hundred seconds of 500MW of thermal energy for 50MW of input (Q= 10). They may be wrong but they're bending metal (well niobium alloys) on the basis they're right or that they can make what they're building perform to that level in the end. If they can't then tokamak fusion is dead as a future power source.
I've not heard much more about the South Koreans and their Dash for Fusion project i.e. skip ITER and DEMO and go straight to a son-of-PROTO based on what we know right now. Supposedly there was some serious money behind it but it seems to have dropped off the radar somewhat.
Nobody really knows since nobody's ever got a significant amount of fusion to work for long enough to figure out the gas mileage, so to speak.
The golden chalice is deuterium-deuterium (D-D) fusion which can be done with just heavy water, D2O which is expensive but abundant (it makes up about 1 part in 40 million of water molecules), it just has to be separated out from regular water using centrifuges or other processes. Assuming a lot of fusion power plants are built then there would be be cost savings per tonne of deuterium produced the same way uranium mining and processing is a lot cheaper today than it was during WWII. D-D fusion is hard though.
The easier road to fusion is deuterium-tritium, so-called D-T fusion but tritium is only produced in small amounts in nuclear fission reactors. There is a way to produce tritium in a working fusion reactor by using a blanket of lithium to absorb neutrons but it's very experimental and unproven. ITER is being built in part to test the idea of Li breeding of tritium and it's likely JET will also be used to test the concept, it's being repurposed as a materials testbed for ITER.
The best performance of a tokamak I know of was the JET run back in the 90s where they got about 22MJ out of plasma in about 1.5 seconds, a rate of 15MW for that time. It was nowhere near "ignition", it took significantly more energy to create that plasma than it emitted while it lasted.
The NIF people talk about "ignition" because that's what they do, it's in their name after all. Magnetic fusion people talk about Q factor. Q=1 is breakeven where the same amount of fusion energy is produced as is pumped in to make and heat the plasma. I think the best Q figure JET has ever achieved is about 0.6 and only for a very brief time.
The ITER tokamak under construction on France is expected to return values of Q > 10 eventually, with 50MW input producing more than 500MW of thermal energy in a fusion plasma that can be sustained for hundreds of seconds and hopefully it won't have to be rebuilt after every run.
Actually it was fusion power that was going to be too cheap to meter but it makes a good story to attribute it to fission plants. The prediction was the product of a marketing executive, not someone with any real knowledge of the science, engineering, finance or commercial operation of any such facility. Makes a great soundbite though, doesn't it?
It IS different in other parts of the world, like here in the UK. Most public ATMs are part of the Link network and debit cards for most of the big banks will work in any of them with no transaction fee.
The next step being rolled out here is contactless debit cards which can be used with a wireless reader to make purchases of up to 20 quid without entering a PIN or otherwise authorising the transaction. I think the idea is the banks will eat the losses from any fraudulent transactions as long as they're for small amounts. The same cards will do chip-and-PIN authorisation for larger amounts.
It seems the volunteer in question was taking people visiting Bletchley Park into the National Museum of Computing next door and acting as a tour guide there rather than working as a guide solely in Bletchley Park. He wasn't employed as a guide by the NMoC and I'm not even sure he or the tour groups he was escorting were paying entry fees to get into the museum; the two separate operations share the site and the buildings and there is no clear physical distinction between the two although the Bletchley Park team are supposedly planning to erect a fence soon).
There are no treaties preventing reprocessing of spent fuel that I know of. Britain, France, Russia and some other countries already reprocess spent fuel, Japan is about to start doing it on a commercial scale. The US could reprocess spent fuel if it wanted to -- President Carter's moratorium on reprocessing was overturned by President Reagan and there was even a start on building a reprocessing plant in the US over a decade ago, but...
A reprocessing plant is very expensive to build and operating it costs money. Its output is fresh fuel materials (U-235, U-238 and some plutonium isotopes) and some concentrated highly-radioactive waste. Right now the minehead price for uranium yellowcake (U3O8) is about $40 per lb so at the moment the costs of reprocessing are much greater than the cost of fresh fuel. The waste is much reduced in mass and volume but it is now very concentrated and more difficult to handle than ten-year-old spent fuel rods sitting in a pool or dry-casked. The waste is usually vitrified, another expense, before being jacketed for longer-term storage and eventual burial.
The current generation of new-build reactors such as the EPR1400 and the APR are based off proven commercial designs like the French Gen2 M310 designed in the 1970s. These new reactors are designed to operate for sixty years or more, their financial underpinnings require them to run that long to repay the expense of licencing, designing and building them now to generate affordable electricity to meet today's energy demands. Magical waste-burning reactors fuelled with pixie-dust and unicorn droppings aren't going to get built any time soon other than maybe as money-no-object research curios and they're especially not going to get built unless they have gold-plated guarantees of reliable functioning for decades generating electricity at 5 cents/kWh.
I live in Scotland which has most of Britain's hydroelectric generating capacity. It totals a bit over 1GW if everything is in use. Right now and for the past few weeks this capacity has been run hard on a use-it-or-lose-it basis since it's been raining heavily due to a series of Atlantic storms and the reservoirs are pretty much full up with more runoff coming in the next few weeks. It's better to generate electricity with that water now at any price than to let it spill over the dams and go to waste.
We don't have much snowpack so after the spring rains production is reduced until the autumn when the reservoirs refill again. They get tapped (so to speak) when the spot market electricity prices rise high enough to justify using up the stored water. Note that the total hydroelectric capacity is less than 3% of the national peak demand and during the drier summer months the output from our hydroelectric stations can fall to a few dozen megawatts. A quick Google suggests Norway has 30GW of installed hydroelectric capacity with a population of five million people, or 6kW/person. In the UK it's 20W/person.
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I got tired of reading godlikeproductions and globalresearch and enenews and the other bullshit sites posting about the Fukushima disaster because they were garbage sources full of fairy tales, improbable conspiracies and Hollywood disaster movie physics. I've not read the item you posted but the link text claims says fuel pellets were blasted thirty kilometres by the force of the explosions. Think about that for a moment, the physics of it, launching ANYTHING that sort of distance requires precision engineering as in large artillery pieces or an explosion that would have levelled the entire site and for kilometres around it too. No giant explosion, site not levelled, no artillery in evidence, bullshit story.
Enenews? Really?
New GenIII reactor designs have a shield/liner that sits between the actual pressure vessel and the core structures that hold the fuel elements and guides for control rods etc. This shield can be removed and replaced during a major refurbishment. It won't stop neutron damage to the vessel but it does cut it down somewhat, extending the reactor's effective life. The GenIII designs are expected to operate within spec for a century absent accident or something unknown appearing in that time (like the Wigner Effect in carbon-moderated reactors) and if nothing much has appeared in the hundreds of LWRs that have operated for forty years and more then it's unlikely something will turn up now.
Even then modern designs like the EPR permit, in theory, the operators to swap out the reactor vessel. GenII designs built the containment structures around the reactor vessel, nowadays it is put in place after most of the nuclear island's concrete has been constructed and it could be removed in a similar manner. It would be a long multiyear undertaking and very expensive so it will probably never happen other than if the vessel fails very early in the reactor's life to justify the cost and effort.
The two Vogtle reactors in Georgia started construction last year as did two new AP1000s Sumner plants in South Carolina, a total of four new starts. The news about the loan guarantees is just that, the loans themselves to pay for construction of the AP1000s had already been agreed. It was expected the guarantees would be issued.
As for long-term investments the US threw an immense amount of taxpayers money into something called the Interstate starting about 80 years ago. How did that work out for you?
I recall reading somewhere that the NRC has a two-year backlog in its approvals process i.e. a power generating company submitting paperwork for a Construction and Operating Licence (COL) today will get it looked at in 2016 at the earliest with a three to five year delay after that for a yes/no decision. The NRC is a US government department hence it's underfunded and woefully understaffed especially in the technical divisions as there are better career opportunities for the qualified engineers needed to go analyse the intensely technical submission documents for a new build.
As for existing plants reaching end-of-life, that's debatable. Usually by the thirty-year mark a plant's non-core units are in train to be replaced, things like steam generators, main pumps etc. Almost all of the current US reactors have upgraded to digital control systems if they were originally built with anaogue controls back in the 1970s. The key irreplaceable parts of a reactor are the reactor vessel and its containment and since they were originally overspecified and overbuilt to an almost ludicrous degree and they have no moving parts in themselves they usually pass inspection with flying colours. It tends to be external factors that will downcheck a reactor -- safety systems, steam generators etc.
If the NRC was to shut down older plants simply because they are old their capacity will be replaced with gas and coal, not nuclear because they're a lot less effort in terms of paperwork and currently they're about as cheap to run assuming no-one cares about the pollution they spew into the atmosphere 24/7.
You could have bought low-dose codeine/ibuprofen or codeine/paracetamol tablets over-the-counter at a pharmacy in the UK. (Reaches into drawer -- Boots own-brand 200mg ibuprofen and 12.8mg codeine tablets, pack of 16 costs about 8 bucks US IIRC, the duty pharamcist would make sure you understood the dosage limits etc. before selling them to you). They would probably done a better job controlling your dental pain than ibuprofen by itself. Anything over 12.8mg of codeine compounded takes a doctor's prescription, usually 30mg (trade name Solpadol) for chronic pain but they are prescribed readily. My landlord gets them for painful gout flareups, for example.
I use the 12.8mg formulation to cope with very occasional migraines, occasionally I raid my landlord's stash of 30mg Solpadol if it's promising to be a bad one. I make sure I don't travel with them to certain countries though as possession of any codeine compound is a criminal offence in some places, like Japan.
I suggested Elon buys a second-hand aircraft carrier and uses that. It would solidify his James-Bond supervillain status and piss off Larry Ellison no end as a bonus.
The continuous-process system envisaged by LFTR enthusiasts needed to purify the molten-salt stream and prevent the reactor from shutting down due to poisoning can be tapped to extract any particular element with a bit of surreptitious work, and that includes extracting pure kickstarter U-235 (which is easy to make a bomb from) or pure kickstarter Pu-239 (trickier to weaponise but still possible) or U-233 bred from thorium (which also works as bomb material but not as well as U-235).
Current conventional reactors produce a mixture of Pu-239 and Pu-240, useless as bomb material, in spent fuel since the operating cycles last for a year or more between refuelling and some of the Pu-239 undergoes another neutron capture to make Pu-240. Pu-239 can't be separated from Pu-240 without great effort; the centrifuges or other enrichment equipment needed could purify U-235 from raw uranium much more easily.
MOX fuel formulations are only a small percentage of Pu, typically something like 6% or so hence the term Mixed-OXide comprising both uranium oxide and plutonium oxide. A MOX fuel element will still have Pu in it after it has spent a cycle in the reactor but much of the original Pu-239 and Pu-240 will have been fissioned. More Pu will have been bred from the U-238 comprising most of the rest of the fuel element but the total inventory of Pu in the spent fuel will have been decreased while producing a significant amount of process heat for electricity generation and other uses such as desalination. The spent fuel rod can of course be reprocessed and the Pu reconstituted as fresh MOX fuel.
I don't know of any proposed LFTR operational cycle that would produce Pu-238 in any significant quantity; breeding up from Th-232 all the way to Pu-238 is a lot of steps requiring several neutron captures and decays with several intermediates which would interrupt the chain if fissioned. Adding Np-238 to the molten-salt fuel might work to make Pu-238 but the only source of Np-238 in quantity is a conventional nuclear reactor...
The LFTR system requires breeding thorium up into U-233 which requires a dense neutron flux, a lot denser than conventional fission reactors. Pu-239 is very good for this but the presence of Pu-240 in the fuel stream degrades that neutron economy as fissioning it produces fewer neutrons than Pu-239. MOX can be burned in existing nuclear reactors with some care to produce useful energy since the U-235 present in the fuel produces a large surplus of neutrons which fissions the Pu-239 and the Pu-240.
No *the LFTR* has not been tested for real.
If you read the fine article you linked to you will discover the reactor in question at Oak Ridge did not use thorium at all. It only used molten salt with U-233 and later on U-235 as fissile material. Breeding thorium up into something fissile in a molten-salt stream is much trickier with all sorts of problems which at the moment have only been dealt with in Powerpoint slides and a lot of handwaving by LFTR proponents.
As for the impossibility of keeping a Pu purification process secret for long I heartily agree. The folks attempting it only need to do it once and succeed for bad things to happen though. The thought of bomb-grade Pu proliferation happening with other technologies is scary enough that billions of dollars are spent every year around the world covering even less likely eventualities. Adding another point-of-leakage of bomb-grade Pu-239 into the outside world is something to be worried about and an additional expense laid at the door of anyone thinking of building a LFTR.
Pu would only be created in a MSR if it was designed to produce it and/or the fuel mix was preloaded with U-238. The problem with LFTR or any other thorium breeder reactor system is that it needs a kickstarter of fissile material, usually a mixture of U-233 or U-235 and Pu-239 to start the breeding process since Th-232 isn't fissile. The kickstarter for a single 1GWe LFTR would probably have enough Pu-239 in pure form to make several implosion-type weapons.
Folks around the world are burning recycled plutonium in commercial power nuclear reactors today. Not in America, for various reasons (mainly due to a lack of native reprocessing capability and some "not invented here" plus the fact that once-through uranium fuel is incredibly cheap at the moment) but it is being done. It's not bomb-grade material, it's the much safer mixed-oxide (MOX) formulation "contaminated" with Pu-240 which spoils it for possible use in bombs even if it was extracted for that use.
No, proposed thorium breeder reactors like the LFTR breed Th-232 up into fissile U-233 and then fission that to produce energy and enough neutrons to continue the breeding cycle. The kickstarter fuel load with U-235 and Pu-239 initiates the breeding operation (hopefully, it's never been tested for real).
Breeding thorium has been done on a small scale in pebble-bed reactors using a small amount of thorium in the pebbles but relying on most of the fissiel fuel being U-235 to provide sufficient neutron flux to do the breeding which was not sustainable otherwise.
A worry with most of the LFTR designs is that commercial companies will have access to bomb-grade Pu-239 which can be chemically extracted from the kickstarter fuel load. MOX fuel for conventional PWRs has too much Pu-240 in the mix to build functional weapons from.
Ummm, no. The economic factor for Super-Phenix shutting down was that it was an engineering prototype that pushed the envelope a bit too far in various directions. It broke in interesting ways, some due to the liquid sodium coolant, some because of the very intense neutron flux in a very small volume. The fact that the Greens fired a few RPG-7s at it in its early days had little to do with its eventual shutdown. This is La Belle France, remember -- see what they did to the Rainbow Warrior for what they think of Greenpeace.
The folks pushing next-generation breeders such as the assorted LFTRs, travelling-wave and other IFRs and the like have learned from the failures of the early breeder designs but it's likely they will run into other whoopsies themselves as they try to run productively for decades on end at 5 cents/kWh.
President Carter's reprocessing ban was in fact overturned by President Reagan. It costs money, lots of it, to reprocess spent fuel and the money to build commercial reprocessing plants wasn't forthcoming until about fifteen years ago when DoE funding was advanced to build a MOX fuel fabrication plant in South Carolina. The pricetag is now $5 billion, the plant is still unfinished and there are no confirmed customers for its MOX fuel in the US despite, it is claimed, generous subsidies. As far as I know there are no commercial reactors using MOX with recycled plutonium in the US at the moment.
Breeder reactors can't earn their way simply producing plutonium fuel other than for military purposes as cost-no-object operations. They need to generate electricity too and the operational experience of breeders over the past few decades is that they are not reliable and cost-effective to run especially these days when fracked gas-fired power generators can deliver electricity wholesale to the grid for about 3 cents/kWh. The French Super-Phenix breeder was intended to produce 1.2GW of electricity but it suffered problems and delays and was eventually shut down in part due to economic factors. Other breeders have had similar problems over the decades.
As for the START process it can take a decade or more to get something both countries can agree to -- President Obama signed off on the latest START agreement but it was begun by President Bush after the groundwork had been laid in President Clinton's term. The US (and Russia too) have to consider there are other unfriendly nuclear powers in existence today such as China with limited stocks of weapons but with intercontinental range. America's ready-for-use stockpile of about 2,000 deliverable warheads has to be able to deter more than Russia.
The Tohoku coastline on the south-eastern side of Honshu where the Fukushima nuclear plants are located is swept by the Kuroshio current, part of the North Pacific circulatory system dispersing material from the coast across the Pacific. Much of the fallout from the Fukushima disaster has already been thoroughly diluted into the ocean and marker isotopes such as Cs-134 (a fission product with a 2-year half-life therefore very little remaining from US nuclear weapons tests in the Pacific in the 1950s to confuse the results) are starting to be detected at very low levels off the US west coast.
There's still significant levels of radioactivity at and around the Chernobyl site, well above international safety limits for permanent human habitation. Animals tend to have short lives anyway, dying of starvation, disease, predation or accident rather than old age so their chances of developing a lethal cancer (the only real ill effect of mild raised levels of radiation) are low since they die of something else beforehand.
I'd be suspicious of regularly eating food grown in the Chernobyl area unless it was thoroughly tested. If I was to work or live there I'd expect my exposure to radiation to be limited with monitoring and if I took enough exposure over a given period I'd move out.
In the case of Fukushima the evacuated areas around the plant are much smaller and less contaminated than at Chernobyl. There was an illustration I saw once layering the Fukushima release plumes map to scale over the Chernobyl exclusion zone -- the entire area in Japan designated off-limits (less than 1000 square km) was about the size of the marker pinpointing the reactor site on the Ukranian map. Even so large parts of the original Japanese exclusion zone have been reopened to permanent occupation and some of the rest can be visited on a restricted basis while decontamination takes place.
"Google Cherynobyl? To this very day it is so radioactive you can't get within 50 to 100 miles of it?"
After the accident/explosion/fire etc. in 1986 the Ukrainian authorities continued to operate the three other undamaged reactors at Chernobyl (they needed the electricity supplies). After a few years folks started running tourist trips to visit the area including the evacuated towns surrounding the damaged reactor. Thousands of workers have been working on the reactor building for decades attempting to entomb it or at least cover it up so it doesn't leak quite as much residual radioactivity as it does even today.
Sure in a Hollywood disaster movie script the Chernobyl site is so radioactive you can't get within 50 to 100 miles of it. However this is real life which is kinda different.
Ah, I just realised you're trolling, aren't you? Silly me.
I did specify D2O as being 1 part in 40 million, not DHO which is a lot more common. Deuterium for plasma fuel needs to be reasonably pure at the moment, it's one of the things the ITER program is tasked with, to see just how crappy the deuterium:hydrogen ratio in fuel can be and still produce good Q levels and burn times. This will reduce the cost of producing fuel in the long run.
I have a vague recollection the Japanese tokamak you mention (the JT-60?) was running on D-D fuel and they calculated that if they had used D-T they'd have got Q>1 but it wasn't set up to run with tritium. A moral victory if not a real achievement. The Japanese are in the ITER consortium and the JT-60 is being rebuilt and upgraded as part of the total research effort, like JET at Culham.
ITER is being built right now and the designers believe it will give them several hundred seconds of 500MW of thermal energy for 50MW of input (Q= 10). They may be wrong but they're bending metal (well niobium alloys) on the basis they're right or that they can make what they're building perform to that level in the end. If they can't then tokamak fusion is dead as a future power source.
I've not heard much more about the South Koreans and their Dash for Fusion project i.e. skip ITER and DEMO and go straight to a son-of-PROTO based on what we know right now. Supposedly there was some serious money behind it but it seems to have dropped off the radar somewhat.
Nobody really knows since nobody's ever got a significant amount of fusion to work for long enough to figure out the gas mileage, so to speak.
The golden chalice is deuterium-deuterium (D-D) fusion which can be done with just heavy water, D2O which is expensive but abundant (it makes up about 1 part in 40 million of water molecules), it just has to be separated out from regular water using centrifuges or other processes. Assuming a lot of fusion power plants are built then there would be be cost savings per tonne of deuterium produced the same way uranium mining and processing is a lot cheaper today than it was during WWII. D-D fusion is hard though.
The easier road to fusion is deuterium-tritium, so-called D-T fusion but tritium is only produced in small amounts in nuclear fission reactors. There is a way to produce tritium in a working fusion reactor by using a blanket of lithium to absorb neutrons but it's very experimental and unproven. ITER is being built in part to test the idea of Li breeding of tritium and it's likely JET will also be used to test the concept, it's being repurposed as a materials testbed for ITER.
The best performance of a tokamak I know of was the JET run back in the 90s where they got about 22MJ out of plasma in about 1.5 seconds, a rate of 15MW for that time. It was nowhere near "ignition", it took significantly more energy to create that plasma than it emitted while it lasted.
The NIF people talk about "ignition" because that's what they do, it's in their name after all. Magnetic fusion people talk about Q factor. Q=1 is breakeven where the same amount of fusion energy is produced as is pumped in to make and heat the plasma. I think the best Q figure JET has ever achieved is about 0.6 and only for a very brief time.
The ITER tokamak under construction on France is expected to return values of Q > 10 eventually, with 50MW input producing more than 500MW of thermal energy in a fusion plasma that can be sustained for hundreds of seconds and hopefully it won't have to be rebuilt after every run.
Actually it was fusion power that was going to be too cheap to meter but it makes a good story to attribute it to fission plants. The prediction was the product of a marketing executive, not someone with any real knowledge of the science, engineering, finance or commercial operation of any such facility. Makes a great soundbite though, doesn't it?
It IS different in other parts of the world, like here in the UK. Most public ATMs are part of the Link network and debit cards for most of the big banks will work in any of them with no transaction fee.
The next step being rolled out here is contactless debit cards which can be used with a wireless reader to make purchases of up to 20 quid without entering a PIN or otherwise authorising the transaction. I think the idea is the banks will eat the losses from any fraudulent transactions as long as they're for small amounts. The same cards will do chip-and-PIN authorisation for larger amounts.
It seems the volunteer in question was taking people visiting Bletchley Park into the National Museum of Computing next door and acting as a tour guide there rather than working as a guide solely in Bletchley Park. He wasn't employed as a guide by the NMoC and I'm not even sure he or the tour groups he was escorting were paying entry fees to get into the museum; the two separate operations share the site and the buildings and there is no clear physical distinction between the two although the Bletchley Park team are supposedly planning to erect a fence soon).
There are no treaties preventing reprocessing of spent fuel that I know of. Britain, France, Russia and some other countries already reprocess spent fuel, Japan is about to start doing it on a commercial scale. The US could reprocess spent fuel if it wanted to -- President Carter's moratorium on reprocessing was overturned by President Reagan and there was even a start on building a reprocessing plant in the US over a decade ago, but...
A reprocessing plant is very expensive to build and operating it costs money. Its output is fresh fuel materials (U-235, U-238 and some plutonium isotopes) and some concentrated highly-radioactive waste. Right now the minehead price for uranium yellowcake (U3O8) is about $40 per lb so at the moment the costs of reprocessing are much greater than the cost of fresh fuel. The waste is much reduced in mass and volume but it is now very concentrated and more difficult to handle than ten-year-old spent fuel rods sitting in a pool or dry-casked. The waste is usually vitrified, another expense, before being jacketed for longer-term storage and eventual burial.
The current generation of new-build reactors such as the EPR1400 and the APR are based off proven commercial designs like the French Gen2 M310 designed in the 1970s. These new reactors are designed to operate for sixty years or more, their financial underpinnings require them to run that long to repay the expense of licencing, designing and building them now to generate affordable electricity to meet today's energy demands. Magical waste-burning reactors fuelled with pixie-dust and unicorn droppings aren't going to get built any time soon other than maybe as money-no-object research curios and they're especially not going to get built unless they have gold-plated guarantees of reliable functioning for decades generating electricity at 5 cents/kWh.
And that's why you can't have nice things.
I live in Scotland which has most of Britain's hydroelectric generating capacity. It totals a bit over 1GW if everything is in use. Right now and for the past few weeks this capacity has been run hard on a use-it-or-lose-it basis since it's been raining heavily due to a series of Atlantic storms and the reservoirs are pretty much full up with more runoff coming in the next few weeks. It's better to generate electricity with that water now at any price than to let it spill over the dams and go to waste.
We don't have much snowpack so after the spring rains production is reduced until the autumn when the reservoirs refill again. They get tapped (so to speak) when the spot market electricity prices rise high enough to justify using up the stored water. Note that the total hydroelectric capacity is less than 3% of the national peak demand and during the drier summer months the output from our hydroelectric stations can fall to a few dozen megawatts. A quick Google suggests Norway has 30GW of installed hydroelectric capacity with a population of five million people, or 6kW/person. In the UK it's 20W/person.