I'd imagine that an extra few hundred megawatts would be very useful in Japan just now. It might give a few hundred thousand people some heat, light and communications that they desperately need.
Routing it onshore would be possible. I believe it's been done before, by the Russians.
Yes, I left the nuclear industry and went into software engineering. The glacial pace of change in the nuclear industry was more than I could bare.
It was caused by lack of political will to develop new nuclear generating capacity, which in turn was caused by public anti-nuclear hysteria. Back in the 1990s it was career suicide for a politician to even hint that nuclear power should be considered as a future energy source.
The British nuclear expertise was given early retirement and the labs closed down.
Gas (from the North Sea and SIberia) was the Future, the electricity market was "deregulated" (actually loaded in favour of gas and other short-term solutions), our old but very reliable and robust powerstation was priced out of the market and we closed.
A mere decade later, we've burnt all our own gas, Russia is run by mafia, and mainstream politicians are finally being forced to consider climate change brought about by burning fossil fuels.
The moratorium on new nuclear build since Sizewell B went up in the late 80's has left us short of generating capacity (we already import 2GW from France under the English Channel) and now we're a bit stuck.
Since we retired our own nuclear expertise we'll be buying new nuclear reactors from France. EDF will be building some, and they'll be of the PWR design...
Britain, where we invented the pre-stressed concrete pressure vessel, the Advanced Gas-Cooled Reactor (capable of producing superheated steam at 650C), the once-through boiler... and we even build a couple of working Fast Reactors (fueled by plutonium - nuclear waste).
If someone as famous as Carmack comes out and says that Direct3D is "better than" OpenGL, and if the PHBs of all the big 3D hardware companies get it into their thick little skulls that Direct3D has won, you can be sure that support for OpenGL will start to be withdrawn for "good business reasons."
Then everyone who doesn't have Windows will not be able to buy new 3D hardware and the OpenGL platform will die. We will be left with legacy hardware and bit-rotting software.
That's good. The fuel cladding should be able to withstand seawater. I don't know too much about BWRs. Presumably these ones use zircalloy cladding for the fuel (similar to PWRs)?
The thing about the seawater is that it is full of impurities, many of which can probably become activated in a neutron flux. I'd imagine that's the least of their worries, just now.
I've undergone accupuncture treatment for various ailments, and I can attest that it works. During accupuncture, you feel very relaxed and afterwords there is a great feeling of "high" from natural opiates produced in the body.
Why it works is not fully understood by rational studies have shown the effects on the brain using MRI scans. I agree that all those "energy points" and stuff is a load of nonsense, but there is an effect, even if the cause is not known.
Before I had accupuncture the first time I made it perfectly clear that I don't believe in mumbo-jumbo and I like my medicine to be evidence-based. My therapist agreed.
How can you make a reactor terror proof?(planes/bombs/espionage)
You can't, you can just minimise the risk. However, a thick concrete shield around a reactor is plenty to stop planes and most bombs. If the bomb is big enough, you've other things to worry about.
You can design a rector such that terrorists can't use it to cause much harm. Similarly with espionage.
Once solar is cheaper than coal we will stop having this stupid discussion; face facts that right now coal/oil/nat gas is much safer, cheaper, and easier to use than nuclear.
Oil (and fossil fuels in general) are NOT safer and cheaper. How many people a year die mining for coal and drilling for oil? What about all those combustion products that we put into the atmosphere that have altered the global climate? Cheap, eh? How many trillions of dollars is it going to cost us to deal with climate change resulting from fossil fuel use?
Solar energy is a finite resource. Human demand for electricity is not. It is human nature to want to develop. There isn't enough solar to meet the demand, and we need to let some sunlight hit the earth's surface for those plants to use to photosynthesize.
Nuclear has a very important role to play. Just now, fission is the best we have, and it's safer and cleaner than almost everything else. OK, solar might play a small part, but it just can't provide us with all that we need. Neither can wind and wave.
The "Nuclear Energy" of which you speak is dated mainly because it was designed in the 1950s and 1960s. That's over half a century ago.
We can do much better now, but the anti-nuclear lobby has prevented us from getting anything built.
Imagine if there was an anti-car lobby with as much power. We'd all (OK a very small number of us would) be driving around in incredibly expensive and patched-up Ford Anglias and Morris Minors today. Everyone else would be going by horse or foot.
There are many factors (as you might expect) that contribute to nuclear safety. The most important is the design of the nuclear reactor. It's very difficult to make a poor design "safe" and a containment dome isn't always possible or useful. For example, gas-cooled reactors could not have containment domes.
The RBMK (Chernobyl) design is intrinsically unsafe from a nuclear physics point of view, as demonstrated by the accident in 1996. Additionally, the safety systems were poor and able to be vetoed (very bad) and the reactor was being run out of its design specification and by people who didn't understand Reactor Physics. In fact, their attitude was one of superstition: the reactor has been good to us in the past, so it'll be good to us today.
Here in the UK there were great changes in the way our nuclear power industry was run following the Chernobyl disaster. The legal framework for the industry was completely overhauled, the way we operated our reactors was radically changed and all of our safety cases and fault studies were revisited, re-analysed and our plant refitted with extra redundant, diverse and segragated safety systems. All of our personnel, from the company directors to the plant operators were retrained.
We are lucky in that most of our reactors are of the gas-cooled variety (AGRs with formerly some Magnoxes). They are pretty intrinsically safe designs, but not perfect. Explosions and meltdowns are either "incredible faults" or highly unlikely. The most likely event that could lead to an offsite release of radioactivity for Magnoxes was a channel fire. At the commercial stations, this never happened. There was one once at Chapel Cross (used to make isotopes for military purposes in addition to electricity) but there was no release from the affected reactor, and they were able to refuel and continue using it.
The concrete pressure vessel stations (AGRs and the two youngest Magnoxes) could not "explode" (burst open). They are too strong: no tertiary containment (containment dome) required. They can't go prompt critical (i.e. no Chernobyl) because of the reactor physics and safety systems. If you tried to do one manually, the reactor would be shut down automatically long before it even got a bit too hot.
We won't be building any more AGRs, though. EDF will probably be building some based on the PWR design in the next few years. PWRs are OK as long as you have plenty of redundant and segregated cooling loops. I think the new ones will be able to post-trip cool on natural convection, so no power required for emergency cooling.
As for your original point, as long as the Russian RBMKs have their safety systems fixed (unable to be take out of service) there should not be another Chernobyl. Another thought: I don't know if these plant have boric acid for emergencies. For water-cooled reactors (e.g. PWR) it is a requirement to have a load of boric acid that can be dumped into the primary coolant to ensure permanent shutdown in the case of an emergency. Boric acid dissolves in the water and the boron absorbs all the neutrons. shutting down the nuclear reactions. It's a permanent shutdown though:-) The Magnoxes had boron dust that could be injected into the coolant gas for such an emergency.
Even when a reactor is successfully shut down, it is still producing 100MW of energy for several days
When a reactor is shut down suddenly (a reactor trip or SCRAM) it continues to produce heat at a rate of 10% of the power it was previously running at. So, if you have a large PWR that can do 2500MW thermal and you trip it (SCRAM) you will have to remove decay heat at a rate of 250MW immediately following the shutdown.
My old Magnox reactors used to do a mere 480MW thermal, so post-trip they did about 48MW thermal. That's still quite a lot of heat with nowhere to go if you don't keep the cooling on.
In the UK we have one commercial PWR, Sizewell B, in Suffolk. This reactor relies on forced circulation of the primary coolant (i.e. the water in the core) for post trip cooling. There are multiple redundant cooling circuits and pumps. Ultimately the heat gets dumped into the North Sea. It is possible to build the cooling circuits in such a way that natural convection of the hot water is sufficient to cool the core post-shutdown. As long as the pressure vessel and primary loop is intact (not unlikely) and the secondary and tertiary (IIRC) loops are also intact, you are laughing. I don't know if Sizewell B can do natural convection. I suspect not..
My old Magnox station was designed in the 1950s with slide rules, copious cups of milky tea and Wile - e - Coyote Acme blueprints. Magnoxes are (were) cooled by carbon dioxide and graphite moderated. The secondary coolant was demineralised water and the tertiary coolant was sea water.
The fault studies determined that, to ensure adequate post-trip cooling for a pressurised reactor, one gas circuit (out of 6) would be enough but at least two (IIRC) had to be in service. (It's been over 10 years since I left, so forgive me if the details are sketchy).
The decay heat (that 48MW post-trip) gradually dies away, and there was a period of time (a few days?) after which you could come down to single circuit cooling. The rationale was, that if that cooling circuit failed (the electric motor driving the gas circulator) you could get another one (of the remaining 5) in service within 24 hours and still not overheat the reactor core. "24 hours" was a nice round number picked out of the air to give plenty of time to get things sorted out.
After a few weeks, the decay heat was so insignificant, that you could depressurise the reactor and introduce air and not really require any cooling at all. We used to do this to one of the two reactors each year for the biennial inspection. Once I spent a fortnight putting a video camera down thousands of fuel channels...
However, in the 1980s and 1990s when RISC workstations became available, they were able to do newfangled more accurate (less pessimistic) fault studies for all the old Magnox reactors, and found some surreptitious happy things:
All of the old Magnoxes were capable of post-trip cooling by natural convection! No forced circulation of the coolant gas required! This was a result of the large difference in height between the reactor gas inlets and the top of the boilers (typically over 100 feet/30 metres).
So as long as your old Magnox reactor had gas in it, and as long as there was cold water in the boilers, if the rods went in and you lost all gas circulators, they wouldn't overheat.
Why does the world still continue to operate (and even build) BWRs? They're a very poor, cheap design. I believe a new one is being built in the USA just now.
There is no secondary cooling circuit, so active steam goes through the turbines. That means that the turbine halls are radioactive to begin with.
The problem we are seeing here is failure of post-trip cooling. This implies a lot of things wrong with the design and possibly maintenance and operation, and I'm sure the full details of what went wrong will be made available to the public after the investigation.
I feel very sorry for the Japanese and everyone else in Japan just now. The best we can hope now is that the lessons learned from this disaster will give the world better and safer nuclear power stations. We need them to survive and prosper as a species.
What does Unix have, that a person can't get from Linux, or BSD, or OSX?
Not a lot, and anyway, "real unix" (Sys VR4) got Open Sourced several years ago now in the form of Solaris.
Not only has the horse bolted, it has run away to pastures new, died of old age and is eating buttercups and daisies in the great field invisibule with Shergar and Red Rum.
You know, it helps if you don't stop reading a post after the first sentence.
What are you on about? I'm an "end user" of the graphics library.
You, know, you're right. after all. I don't play games nowadays, so why the heck would I want 3D? I'm 36 years old. It's been 10 years since I bought a game. I suppose it doesn't matter if no one but Microsoft customers can run hardware-accelerated 3D code on their computers.
Because I don't want to have to buy a Microsoft-installed computer (expensive, restrictive, unreliable. insecure, user-unfriendly) just to do some 3D stuff.
On what other operating systems does Direct3D run? OpenGL, for all its faults, is an Open Standard and there are several compatible, competing implementations including Open Source ones (Mesa).
OK, so I'm a loony and the doctor gives me pills...
Don't worry, I don't think it could have sounded any better in stereo unless someone thought it was a pizza and put it in the oven at gas mark 6.
One of the record shops I frequent has seen a big upturn in sales of Analogue media in the past year. his biggest seller was the Flaming Lips cover of Dark Side of the Moon. Great Album.
Jesus H. Christ. A medium with inferior sound quality playing music by people with no originality.
Slashdot Mirror
But those sound recordings played backwards still creep me out...
I think they're pretty cool myself.
Braille?
I'd imagine that an extra few hundred megawatts would be very useful in Japan just now. It might give a few hundred thousand people some heat, light and communications that they desperately need.
Routing it onshore would be possible. I believe it's been done before, by the Russians.
Yes, I left the nuclear industry and went into software engineering. The glacial pace of change in the nuclear industry was more than I could bare.
It was caused by lack of political will to develop new nuclear generating capacity, which in turn was caused by public anti-nuclear hysteria. Back in the 1990s it was career suicide for a politician to even hint that nuclear power should be considered as a future energy source.
The British nuclear expertise was given early retirement and the labs closed down.
Gas (from the North Sea and SIberia) was the Future, the electricity market was "deregulated" (actually loaded in favour of gas and other short-term solutions), our old but very reliable and robust powerstation was priced out of the market and we closed.
A mere decade later, we've burnt all our own gas, Russia is run by mafia, and mainstream politicians are finally being forced to consider climate change brought about by burning fossil fuels.
The moratorium on new nuclear build since Sizewell B went up in the late 80's has left us short of generating capacity (we already import 2GW from France under the English Channel) and now we're a bit stuck.
Since we retired our own nuclear expertise we'll be buying new nuclear reactors from France. EDF will be building some, and they'll be of the PWR design...
Britain, where we invented the pre-stressed concrete pressure vessel, the Advanced Gas-Cooled Reactor (capable of producing superheated steam at 650C), the once-through boiler... and we even build a couple of working Fast Reactors (fueled by plutonium - nuclear waste).
Ho hum.
Interesting.
The fact that I'm having to bother to explain this is really sad. It means lots of people are out there reinventing the wheel.
Reinventing the wheel can be fun and educational.
It's not usually a good idea when working in a competitive business, though.
If someone as famous as Carmack comes out and says that Direct3D is "better than" OpenGL, and if the PHBs of all the big 3D hardware companies get it into their thick little skulls that Direct3D has won, you can be sure that support for OpenGL will start to be withdrawn for "good business reasons."
Then everyone who doesn't have Windows will not be able to buy new 3D hardware and the OpenGL platform will die. We will be left with legacy hardware and bit-rotting software.
How does writing to a rendering engine help?
That's good. The fuel cladding should be able to withstand seawater. I don't know too much about BWRs. Presumably these ones use zircalloy cladding for the fuel (similar to PWRs)?
The thing about the seawater is that it is full of impurities, many of which can probably become activated in a neutron flux. I'd imagine that's the least of their worries, just now.
I've undergone accupuncture treatment for various ailments, and I can attest that it works. During accupuncture, you feel very relaxed and afterwords there is a great feeling of "high" from natural opiates produced in the body.
Why it works is not fully understood by rational studies have shown the effects on the brain using MRI scans. I agree that all those "energy points" and stuff is a load of nonsense, but there is an effect, even if the cause is not known.
Before I had accupuncture the first time I made it perfectly clear that I don't believe in mumbo-jumbo and I like my medicine to be evidence-based. My therapist agreed.
How can you make a reactor terror proof?(planes/bombs/espionage)
You can't, you can just minimise the risk. However, a thick concrete shield around a reactor is plenty to stop planes and most bombs. If the bomb is big enough, you've other things to worry about.
You can design a rector such that terrorists can't use it to cause much harm. Similarly with espionage.
Once solar is cheaper than coal we will stop having this stupid discussion; face facts that right now coal/oil/nat gas is much safer, cheaper, and easier to use than nuclear.
Oil (and fossil fuels in general) are NOT safer and cheaper. How many people a year die mining for coal and drilling for oil? What about all those combustion products that we put into the atmosphere that have altered the global climate? Cheap, eh? How many trillions of dollars is it going to cost us to deal with climate change resulting from fossil fuel use?
Solar energy is a finite resource. Human demand for electricity is not. It is human nature to want to develop. There isn't enough solar to meet the demand, and we need to let some sunlight hit the earth's surface for those plants to use to photosynthesize.
Nuclear has a very important role to play. Just now, fission is the best we have, and it's safer and cleaner than almost everything else. OK, solar might play a small part, but it just can't provide us with all that we need. Neither can wind and wave.
Nuclear Energy is dated, and its time is past.
The "Nuclear Energy" of which you speak is dated mainly because it was designed in the 1950s and 1960s. That's over half a century ago.
We can do much better now, but the anti-nuclear lobby has prevented us from getting anything built.
Imagine if there was an anti-car lobby with as much power. We'd all (OK a very small number of us would) be driving around in incredibly expensive and patched-up Ford Anglias and Morris Minors today. Everyone else would be going by horse or foot.
"Containment domes" are not a silver bullet.
There are many factors (as you might expect) that contribute to nuclear safety. The most important is the design of the nuclear reactor. It's very difficult to make a poor design "safe" and a containment dome isn't always possible or useful. For example, gas-cooled reactors could not have containment domes.
The RBMK (Chernobyl) design is intrinsically unsafe from a nuclear physics point of view, as demonstrated by the accident in 1996. Additionally, the safety systems were poor and able to be vetoed (very bad) and the reactor was being run out of its design specification and by people who didn't understand Reactor Physics. In fact, their attitude was one of superstition: the reactor has been good to us in the past, so it'll be good to us today.
Here in the UK there were great changes in the way our nuclear power industry was run following the Chernobyl disaster. The legal framework for the industry was completely overhauled, the way we operated our reactors was radically changed and all of our safety cases and fault studies were revisited, re-analysed and our plant refitted with extra redundant, diverse and segragated safety systems. All of our personnel, from the company directors to the plant operators were retrained.
We are lucky in that most of our reactors are of the gas-cooled variety (AGRs with formerly some Magnoxes). They are pretty intrinsically safe designs, but not perfect. Explosions and meltdowns are either "incredible faults" or highly unlikely. The most likely event that could lead to an offsite release of radioactivity for Magnoxes was a channel fire. At the commercial stations, this never happened. There was one once at Chapel Cross (used to make isotopes for military purposes in addition to electricity) but there was no release from the affected reactor, and they were able to refuel and continue using it.
The concrete pressure vessel stations (AGRs and the two youngest Magnoxes) could not "explode" (burst open). They are too strong: no tertiary containment (containment dome) required. They can't go prompt critical (i.e. no Chernobyl) because of the reactor physics and safety systems. If you tried to do one manually, the reactor would be shut down automatically long before it even got a bit too hot.
We won't be building any more AGRs, though. EDF will probably be building some based on the PWR design in the next few years. PWRs are OK as long as you have plenty of redundant and segregated cooling loops. I think the new ones will be able to post-trip cool on natural convection, so no power required for emergency cooling.
As for your original point, as long as the Russian RBMKs have their safety systems fixed (unable to be take out of service) there should not be another Chernobyl. Another thought: I don't know if these plant have boric acid for emergencies. For water-cooled reactors (e.g. PWR) it is a requirement to have a load of boric acid that can be dumped into the primary coolant to ensure permanent shutdown in the case of an emergency. Boric acid dissolves in the water and the boron absorbs all the neutrons. shutting down the nuclear reactions. It's a permanent shutdown though :-) The Magnoxes had boron dust that could be injected into the coolant gas for such an emergency.
Even when a reactor is successfully shut down, it is still producing 100MW of energy for several days
When a reactor is shut down suddenly (a reactor trip or SCRAM) it continues to produce heat at a rate of 10% of the power it was previously running at. So, if you have a large PWR that can do 2500MW thermal and you trip it (SCRAM) you will have to remove decay heat at a rate of 250MW immediately following the shutdown.
My old Magnox reactors used to do a mere 480MW thermal, so post-trip they did about 48MW thermal. That's still quite a lot of heat with nowhere to go if you don't keep the cooling on.
In the UK we have one commercial PWR, Sizewell B, in Suffolk. This reactor relies on forced circulation of the primary coolant (i.e. the water in the core) for post trip cooling. There are multiple redundant cooling circuits and pumps. Ultimately the heat gets dumped into the North Sea. It is possible to build the cooling circuits in such a way that natural convection of the hot water is sufficient to cool the core post-shutdown. As long as the pressure vessel and primary loop is intact (not unlikely) and the secondary and tertiary (IIRC) loops are also intact, you are laughing. I don't know if Sizewell B can do natural convection. I suspect not..
My old Magnox station was designed in the 1950s with slide rules, copious cups of milky tea and Wile - e - Coyote Acme blueprints. Magnoxes are (were) cooled by carbon dioxide and graphite moderated. The secondary coolant was demineralised water and the tertiary coolant was sea water.
The fault studies determined that, to ensure adequate post-trip cooling for a pressurised reactor, one gas circuit (out of 6) would be enough but at least two (IIRC) had to be in service. (It's been over 10 years since I left, so forgive me if the details are sketchy).
The decay heat (that 48MW post-trip) gradually dies away, and there was a period of time (a few days?) after which you could come down to single circuit cooling. The rationale was, that if that cooling circuit failed (the electric motor driving the gas circulator) you could get another one (of the remaining 5) in service within 24 hours and still not overheat the reactor core. "24 hours" was a nice round number picked out of the air to give plenty of time to get things sorted out.
After a few weeks, the decay heat was so insignificant, that you could depressurise the reactor and introduce air and not really require any cooling at all. We used to do this to one of the two reactors each year for the biennial inspection. Once I spent a fortnight putting a video camera down thousands of fuel channels...
However, in the 1980s and 1990s when RISC workstations became available, they were able to do newfangled more accurate (less pessimistic) fault studies for all the old Magnox reactors, and found some surreptitious happy things:
All of the old Magnoxes were capable of post-trip cooling by natural convection! No forced circulation of the coolant gas required! This was a result of the large difference in height between the reactor gas inlets and the top of the boilers (typically over 100 feet/30 metres).
So as long as your old Magnox reactor had gas in it, and as long as there was cold water in the boilers, if the rods went in and you lost all gas circulators, they wouldn't overheat.
Yes, superstition is an innate part of human nature.
China does not really rely on superstitions
Have you seen Chinese medicine?
Why does the world still continue to operate (and even build) BWRs? They're a very poor, cheap design. I believe a new one is being built in the USA just now.
There is no secondary cooling circuit, so active steam goes through the turbines. That means that the turbine halls are radioactive to begin with.
The problem we are seeing here is failure of post-trip cooling. This implies a lot of things wrong with the design and possibly maintenance and operation, and I'm sure the full details of what went wrong will be made available to the public after the investigation.
I feel very sorry for the Japanese and everyone else in Japan just now. The best we can hope now is that the lessons learned from this disaster will give the world better and safer nuclear power stations. We need them to survive and prosper as a species.
What does Unix have, that a person can't get from Linux, or BSD, or OSX?
Not a lot, and anyway, "real unix" (Sys VR4) got Open Sourced several years ago now in the form of Solaris.
Not only has the horse bolted, it has run away to pastures new, died of old age and is eating buttercups and daisies in the great field invisibule with Shergar and Red Rum.
You know, it helps if you don't stop reading a post after the first sentence.
What are you on about? I'm an "end user" of the graphics library.
You, know, you're right. after all. I don't play games nowadays, so why the heck would I want 3D? I'm 36 years old. It's been 10 years since I bought a game. I suppose it doesn't matter if no one but Microsoft customers can run hardware-accelerated 3D code on their computers.
DirectX, OpenGL.... why should the end user care?
Because I don't want to have to buy a Microsoft-installed computer (expensive, restrictive, unreliable. insecure, user-unfriendly) just to do some 3D stuff.
On what other operating systems does Direct3D run? OpenGL, for all its faults, is an Open Standard and there are several compatible, competing implementations including Open Source ones (Mesa).
OK, so I'm a loony and the doctor gives me pills...
You think we are in bad shape now? Wait until automation hits the service industry.
Congratulations, you have just won the Internet!
But when a software company, usually proprietary, is ran good
Ran well.
Run well.
Vi is better L0ser!
Vim or elvis?
Yes, and emacs has that built-in.
since I bought my first LP (Sgt Pepper in Mono).
Don't worry, I don't think it could have sounded any better in stereo unless someone thought it was a pizza and put it in the oven at gas mark 6.
One of the record shops I frequent has seen a big upturn in sales of Analogue media in the past year. his biggest seller was the Flaming Lips cover of Dark Side of the Moon. Great Album.
Jesus H. Christ. A medium with inferior sound quality playing music by people with no originality.
Can things possibly get any worse?
Android isn't really Linux. Linux is basically a bootloader for it.
That's one mighty large, over-engineered bootloader!. Why didn't they just use uBoot?