That slag then has the geometrical configuration to do some more fission.
Does it? For this enrichment level I believe a chain reaction on fast neutrons isn't possible, so it would need to be moderated. The intact core is fairly close to an optimally reactive configuration, it's not very likely that the meltdown would produce something with the appropriate fuel and moderator geometry to go critical, especially if the water's borated.
Well yes it's nasty, but hazardous material handling isn't new to the nuclear business. Is the toxicity that much worse than, say, the radioactivity of sodium as used in fast breeders?
The designs I've seen have the core and coolant in an underground tank, with any pipe entries and so forth above the level of the core - so you can't have a loss of coolant unless you can find a way to make liquids flow uphill. I suppose in an extreme accident it could boil, but that's where the high boiling point and passive cooling capability come in - a lot better than a light water reactor, where a loss of coolant is depressingly easy and needs active engineered systems to handle.
Decommissioning costs are much lower than construction costs thanks to the time value of money - the construction costs are penalised by interest charges, decommissioning costs are helped by them. Given that decommissioning will happen maybe 60 years after construction, this makes a huge difference and effectively makes decommissioning costs very small.
As for liquid salt - cooling stuff with molten beryllium fluoride? How nuts can you get?
Why is that nuts? It has a high heat capacity, high boiling point (no pressure required, making a loss of coolant accident less likely) and is relatively unreactive. Beryllium compounds are toxic but industry handles a lot worse.
Hydro's limited, wind's somewhat expensive and intermittent and solar's very expensive and intermittent. There's no easy answer.
Coal's a valid comparison because it's the most used fossil fuel for electricity, and large numbers of coal plants are under construction worldwide. Wind and solar are small fry in comparson.
Nuclear is a bit different in that there are other ways to generate electricity (but they suck in different ways), but there's really no practical substitute for oil at the moment, so I suspect oil accidents will cause a lot of heated debate but won't have a significant effect on its production overall.
I don't think Tepco's response has been too bad overall (though information isn't clear yet) - the plant was subjected to a challenge beyond its design basis, which is pretty much "no guarantees" territory. Clearly the design basis was inadequate, but that isn't the fault of the people trying to deal with the accident now. Still, at least the issues had been recognised in the industry, and some more modern nuclear designs don't require external/diesel power for safety.
People coming out with untrue statements (coal CO2 is actually depleted in C-14 compared with natural levels) is a different matter of course. As is deflecting legitimate criticism with a "he does it too" argument.
However I don't think you can assess a technology in isolation. Nuclear opponents like to point out the bad sides of nuclear as a direct argument as to why it shouldn't be used. If you look at it that way, why would you want something that has even a small risk of severe accidents? Seems obvious. But to have a *meaningful* discussion about energy technology you must weigh that against the downsides of other forms of energy (or of having less energy), because ultimately you're going to have to choose something - and that will have its own disadvantages.
The widespread consequences of the BP spill were economic damage rather than injuries. Is that worse than a large number of deaths in a small local area?
The Fukushima situation is less clear though, as we don't have a good idea of the effects of low-dose radiation. They could range from no injuries to a certain number of early deaths from cancer. I just find it interesting why certain hazards are practically ignored (e.g. fossil fuels, road accidents) while others receive major attention (nuclear power, plane crashes, terrorism) despite being rarer and overall harming far fewer people.
Uranium is comparable to oil in the sense that once it's gone it's gone..
True enough, but why not make the best use of it while it's there? It's not as if U-235 is useful for much else. By the time it runs out we should have a better technology, but why penalise ourselves in the meantime by using polluting technologies like coal or immature and expensive technologies like solar? If you're going to refuse to use something because it might run out one day, then it's effectively *already* run out.
That's all true, but at least you have some choice as to what isotopes you end up with - i.e. you can avoid the easily released nasties like iodine and caesium. Radioactive iron (in the form of steel) isn't going anywhere too easily, and the half life is quite short.
As a remaining Vista user, I can't see the point in forking out £80 for Windows 7, and my existing PC is more than powerful enough for what I need. I doubt I'm the only one.
The primary containment was inerted (oxygen free), which is a pretty good way of preventing hydrogen explosions, better than recombiners. The problem was that the hydrogen somehow got out into the non-inerted reactor building, where it built to explosive levels - and then exploded. So I guess the question is why - were they unable to vent it outside? Did the venting system fail and leak? Did the primary containment pressure exceed design limits, causing a leak into the reactor building - and if so, why was this allowed to happen?
It may be a while before we have an accurate answer.
What makes you believe this? A wind power plant is faster build up than a new coal plant or nuclear plant.
The issue is it doesn't scale. At low percentage it's fine, but if you want 50% wind you run into big issues with intermittency - overproduction some of the time, underproduction the rest. That means you need storage, which isn't straightforward at all. Pumped storage hydro is about the best, but that costs money, has an environmental impact, a round-trip efficiency of about 75% and the geography isn't suitable everywhere.
Assuming you live in the USA you have plenty of place in your desserts to build a thermal solar plant. Both options would be much cheaper than a coal or nuclear plant, more reliable and had low running costs.
I don't think so. Onshore wind is reasonably close (if you ignore intermittency), but not solar.
Its radiotoxicity is very significant, more so than its chemical toxicist. Ingested alpha emitters are nasty - Thorotrast was highly carcinogenic despite Thorium having a 14 billion year long half life and so being only weakly radioactive.
Of course, Thorotrast was ingested in huge quantities, which won't happen for this plutonium.
The SSC was three times the radius, which explains how it was going to achieve three times the energy, as you're basically limited by how strong a magnetic field you can make to bend the particles around the ring. And its sheer sze must have also been a big part of why it was so damn expensive.
I'd recommend Blake's 7 over Doctor Who, to be sure. Much more adult themed - don't forget that Doctor Who is more or less a children's show, varying with doctor, writer and era.
But if we're going with Who, my favourites have always been the Pertwee and Baker ones. They also have sensible pacing - the earliest being painfully glacial and the modern ones look like everyone involved was on cocaine when they made them.
Maybe, but the original poster criticised Microsoft for merely following. Apple, of course, did exactly the same - just more successfully. How much of that success was due to technical merit and how much was due to good marketing, of course, is a different matter.
ISPs like Sky or Be are available to most people, and they don't have caps, or worse, traffic shaping.
Would I be a naive fool by suggesting that they should simply charge for usage based on what it costs to provide the network capacity, plus a reasonable profit margin? Yes, I probably would...
Your "proper reactors" in the US also require active decay heat removal to prevent meltdowns. In fact, they're very similar to the ones in Japan. You can stop the chain reaction easily enough, but you can't stop the heat produced from radioactive decay of the fission products.
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That slag then has the geometrical configuration to do some more fission.
Does it? For this enrichment level I believe a chain reaction on fast neutrons isn't possible, so it would need to be moderated. The intact core is fairly close to an optimally reactive configuration, it's not very likely that the meltdown would produce something with the appropriate fuel and moderator geometry to go critical, especially if the water's borated.
Well yes it's nasty, but hazardous material handling isn't new to the nuclear business. Is the toxicity that much worse than, say, the radioactivity of sodium as used in fast breeders?
The designs I've seen have the core and coolant in an underground tank, with any pipe entries and so forth above the level of the core - so you can't have a loss of coolant unless you can find a way to make liquids flow uphill. I suppose in an extreme accident it could boil, but that's where the high boiling point and passive cooling capability come in - a lot better than a light water reactor, where a loss of coolant is depressingly easy and needs active engineered systems to handle.
Decommissioning costs are much lower than construction costs thanks to the time value of money - the construction costs are penalised by interest charges, decommissioning costs are helped by them. Given that decommissioning will happen maybe 60 years after construction, this makes a huge difference and effectively makes decommissioning costs very small.
As for liquid salt - cooling stuff with molten beryllium fluoride? How nuts can you get?
Why is that nuts? It has a high heat capacity, high boiling point (no pressure required, making a loss of coolant accident less likely) and is relatively unreactive. Beryllium compounds are toxic but industry handles a lot worse.
The LHC isn't intended to specifically investigate the standard model, though.
Hydro's limited, wind's somewhat expensive and intermittent and solar's very expensive and intermittent. There's no easy answer.
Coal's a valid comparison because it's the most used fossil fuel for electricity, and large numbers of coal plants are under construction worldwide. Wind and solar are small fry in comparson.
Nuclear is a bit different in that there are other ways to generate electricity (but they suck in different ways), but there's really no practical substitute for oil at the moment, so I suspect oil accidents will cause a lot of heated debate but won't have a significant effect on its production overall.
I don't think Tepco's response has been too bad overall (though information isn't clear yet) - the plant was subjected to a challenge beyond its design basis, which is pretty much "no guarantees" territory. Clearly the design basis was inadequate, but that isn't the fault of the people trying to deal with the accident now. Still, at least the issues had been recognised in the industry, and some more modern nuclear designs don't require external/diesel power for safety.
People coming out with untrue statements (coal CO2 is actually depleted in C-14 compared with natural levels) is a different matter of course. As is deflecting legitimate criticism with a "he does it too" argument.
However I don't think you can assess a technology in isolation. Nuclear opponents like to point out the bad sides of nuclear as a direct argument as to why it shouldn't be used. If you look at it that way, why would you want something that has even a small risk of severe accidents? Seems obvious. But to have a *meaningful* discussion about energy technology you must weigh that against the downsides of other forms of energy (or of having less energy), because ultimately you're going to have to choose something - and that will have its own disadvantages.
The widespread consequences of the BP spill were economic damage rather than injuries. Is that worse than a large number of deaths in a small local area?
The Fukushima situation is less clear though, as we don't have a good idea of the effects of low-dose radiation. They could range from no injuries to a certain number of early deaths from cancer. I just find it interesting why certain hazards are practically ignored (e.g. fossil fuels, road accidents) while others receive major attention (nuclear power, plane crashes, terrorism) despite being rarer and overall harming far fewer people.
Uranium is comparable to oil in the sense that once it's gone it's gone..
True enough, but why not make the best use of it while it's there? It's not as if U-235 is useful for much else. By the time it runs out we should have a better technology, but why penalise ourselves in the meantime by using polluting technologies like coal or immature and expensive technologies like solar? If you're going to refuse to use something because it might run out one day, then it's effectively *already* run out.
167 deaths are just an irrelevance, I'm sure. After all, it didn't cost anyone else any money, so who cares, right?
Since we have to produce power somehow, why is it unreasonable to compare the hazards of different major power sources?
Flue gas scrubbers, while pretty good, aren't 100% effective - so some pollutants are still released. Not to mention CO2.
That's all true, but at least you have some choice as to what isotopes you end up with - i.e. you can avoid the easily released nasties like iodine and caesium. Radioactive iron (in the form of steel) isn't going anywhere too easily, and the half life is quite short.
As a remaining Vista user, I can't see the point in forking out £80 for Windows 7, and my existing PC is more than powerful enough for what I need. I doubt I'm the only one.
The primary containment was inerted (oxygen free), which is a pretty good way of preventing hydrogen explosions, better than recombiners. The problem was that the hydrogen somehow got out into the non-inerted reactor building, where it built to explosive levels - and then exploded. So I guess the question is why - were they unable to vent it outside? Did the venting system fail and leak? Did the primary containment pressure exceed design limits, causing a leak into the reactor building - and if so, why was this allowed to happen?
It may be a while before we have an accurate answer.
It doesn't do PAL - I think colour broadcasts at that time would be optimistic (OK, Baird did mechanical colour TV in 1928, and electronic in 1939).
It's the long-obsolete 405 line standard.
What makes you believe this? A wind power plant is faster build up than a new coal plant or nuclear plant.
The issue is it doesn't scale. At low percentage it's fine, but if you want 50% wind you run into big issues with intermittency - overproduction some of the time, underproduction the rest. That means you need storage, which isn't straightforward at all. Pumped storage hydro is about the best, but that costs money, has an environmental impact, a round-trip efficiency of about 75% and the geography isn't suitable everywhere.
Assuming you live in the USA you have plenty of place in your desserts to build a thermal solar plant. Both options would be much cheaper than a coal or nuclear plant, more reliable and had low running costs.
I don't think so. Onshore wind is reasonably close (if you ignore intermittency), but not solar.
Its radiotoxicity is very significant, more so than its chemical toxicist. Ingested alpha emitters are nasty - Thorotrast was highly carcinogenic despite Thorium having a 14 billion year long half life and so being only weakly radioactive.
Of course, Thorotrast was ingested in huge quantities, which won't happen for this plutonium.
15 years later and at 1/3 the energy.
And 10 times the design luminosity.
The SSC was three times the radius, which explains how it was going to achieve three times the energy, as you're basically limited by how strong a magnetic field you can make to bend the particles around the ring. And its sheer sze must have also been a big part of why it was so damn expensive.
I'd recommend Blake's 7 over Doctor Who, to be sure. Much more adult themed - don't forget that Doctor Who is more or less a children's show, varying with doctor, writer and era.
But if we're going with Who, my favourites have always been the Pertwee and Baker ones. They also have sensible pacing - the earliest being painfully glacial and the modern ones look like everyone involved was on cocaine when they made them.
Maybe, but the original poster criticised Microsoft for merely following. Apple, of course, did exactly the same - just more successfully. How much of that success was due to technical merit and how much was due to good marketing, of course, is a different matter.
They failed when they tried to follow Apple into the MP3 player market, and now they are planning on following Apple into the mobile phone market?!
Apple were not the first into either of those markets, so I don't know why you'd say "follow Apple".
ISPs like Sky or Be are available to most people, and they don't have caps, or worse, traffic shaping.
Would I be a naive fool by suggesting that they should simply charge for usage based on what it costs to provide the network capacity, plus a reasonable profit margin? Yes, I probably would...
Your "proper reactors" in the US also require active decay heat removal to prevent meltdowns. In fact, they're very similar to the ones in Japan. You can stop the chain reaction easily enough, but you can't stop the heat produced from radioactive decay of the fission products.
It's HFC, which is why they're limiting uploads but not downloads - this technology is very asymmetric.