Before and after shots;
http://www.nytimes.com/interactive/2...sunami.html?hp
Before and after shots;
http://www.nytimes.com/interactive/2...sunami.html?hp
sig removed by Zak33
Hot graphite + water= big problems.
Anyway,the RBMK reactors were designed to be relatively cheap to build and could refuelled without the reactor being shut down. On top of this they were used for Plutonium production for the Soviet nuclear weapons programme.
However,most of the recent Russian reactors are of the VVER type which is a PWR reactor.
For FFS the overreaction has started:
http://www.belfasttelegraph.co.uk/ne...-15113711.html
When has Switzerland been hit by a magnitude 8.9 earthquake in the last 1000 years?
Any sodding power plant when hit by such an earthquake would be damaged or fully destroyed.
Next they will be banning construction of hydro-electric plants in Europe since a magnitude 8.9 earthquake could breach a dam.
Last edited by CAT-THE-FIFTH; 14-03-2011 at 03:55 PM.
Cat - Quite, the Register hit the nail on the head - as usual. Basically sums up what I've said in my last two posts
Only thing I'd comment on is that they neglected to point out that some of the backup systems didn't kick in soon enough, which is a bit concerning, although I think overall a good job is being done of containing the situation.
Although their analysis is slightly incorrect RE physics:
"As the hot cores ceased to be cooled by the water which is used to extract power from them, control rods would have remained withdrawn and a runaway chain reaction could have ensued – probably resulting in the worst thing that can happen to a properly designed nuclear reactor: a core meltdown in which the superhot fuel rods actually melt and slag down the whole core into a blob of molten metal."
A runaway chain reaction does not happen in modern reactors. As the coolant boils off, the reactor tends to sub-criticality because the cavitation in the water - bubbles - decrease the amount of moderation; neutrons are not slowed as much and the rate of reaction decerases. For lay-scientists - we want slow neutrons in nuclear power stations because there is a higher probability of them initiating a fission reaction with the fuel.
The latter part is correct though, meltdown can happen, but this is not due to runaway fission. It is due to products from the fission reaction undergoing beta decay, electron/positron emission, heating the surroundings. It can get enough to cause the fuel rods to melt.
I've replied to the Reg article to that effect, it's a great attempt at alleviating public tension, but I do wish they'd get it right!
Last edited by Whiternoise; 14-03-2011 at 04:04 PM.
I'm going off one of those sensationalist news sources, but I don't think the quake itself was the problem - the plants apparently did what they were meant to when the quake happened and shut themselves down. That alone wouldn't cause any great concern. The problem was the quake combined with the tsunami, with the tsunami knocking out the backup generators, used for cooling.
Of course, I may have just dreamt the above.
Best Article so far. From someone who konws what they are talking about. Defence in depth.
http://bravenewclimate.com/2011/03/1...e-explanation/
Last edited by Phage; 14-03-2011 at 04:46 PM.
Society's to blame,
Or possibly Atari.
watercooled (17-03-2011)
Oh great!!
Now they have started here in Blighty:
http://www.mirror.co.uk/news/politic...5875-22989326/
"In the wake of explosions at the Fukushima power plant following the earthquake and tsunami which hit Japan on Friday, Liberal Democrat Energy Secretary Chris Huhne said the UK would be looking at the lessons that could be learned.
He said that while there was no reason to expect similar seismic activity in the UK, officials were taking the situation extremely seriously."
""In opposition Chris Huhne stated clearly that the success of Britain's wind power industry made proposed new nuclear plants redundant.
"He recently shifted position in government, but we hope he'll now put all his effort into ensuring Britain maintains its internationally competitive lead in safe offshore wind, wave and tidal power."
I am not against increasing the amount of renewable power generated in the UK but people have to be realistic. Expecting a country of over 65 million people to generate all of its electricity from renewable power sources in the next 20 years is naive.
Remember,a lot of the environmental groups are against hydroelectricity and even think that ITER is an expensive toy.
At least some people have some common sense:
http://www.maldonandburnhamstandard....nuclear_group/
I hate to think what will happen if a tsunami or an earthquake hits a wind farm and the blades go flying off and kill some people.
They will probably end up banning wind turbines too.
Last edited by CAT-THE-FIFTH; 14-03-2011 at 04:56 PM.
Im glad you have piped up about this Cat as i heard them saying something on TV/Radio the other day about it and i couldn't believe what i was hearing. The reason these nuclear events have been contained to the level they have is from learning from previous mistakes, the threat to the surrounding areas has very little to do with human error or serious design flaw but more to do with a completely uncontrollable natural disaster. As devastating as it is, its completely insane to suggest that this kind of thing can really be avoided by alternative energy methods, as you quite rightly mention above, if any kind of large scale energy producing facility is hit by a multitude of natural disasters, it will have bad consequences for the surrounding area. We cant keep going around and banning things.
CAT-THE-FIFTH (14-03-2011)
Good article. I am in agreement that this proves the safety and resilience of nuclear power plants. However, a couple of things did stand out for me: -
No idea how accurate that is, but that seems like rather a rudimentary error; especially considering how relatively well everything else had gone.This is where things started to go seriously wrong. The external power generators could not be connected to the power plant (the plugs did not fit). So after the batteries ran out, the residual heat could not be carried away any more.
Also the point about the reactors being offline 4-5 years to check everything seems extremely long. The article mentions doing this for half of the reactors. You could argue that is still cheaper and quicker than building a new plant (no idea if Japan's other types of power plants are as resilient), but does suggest that you don't want to put all your eggs in one basket (again, no idea if a similiar time scale is required for other types of plants).
The reason Fukushima hasn't been a lot worse is that we take nuclear power safety very seriously these days. It takes four to five years for some of the mid-range half life materials to decay so perhaps that's what he's alluding to.
I doubt it's cheaper to build a new one, nor would take less time. Nuclear plants don't just get planning permission, you have to sketch out the ideas many years in advance - for safety reasons as well as notifying locals. Suffice to say they have to wait at least 5 years before they could start rebuilding on top of the now-defunct reactors.
Sorry, I meant it in a nuclear vs fossil fuel power plant sort of way. If a fossil fuel power plant isn't as resilient (not sure if that's the case though) and was more likely to fall down, then a nuclear one would still be back up and running before replacing a fallen plant.
Fossil fuel plants require a lot less infrastructure - or at least, less safety (i.e. no need for containment). If you run a gas plant, you simply shut off the gas. If you run a coal plant, you stop shovelling coal. The trouble with nuclear is that once it gets going, it takes a while to stop it - you might say it's got more momentum than fossil fuels. You have the risk of all your fuel burning; all that coal can create one massive fire.
While they may be less resilient, they don't have the same sorts of trials to contend with as nuclear. I suspect it's easier to go fossil for short term power; they scale very well, are cheap and require little more than a furnace and some pipes for the water. Nowadays we bother a lot about efficiency, but that's academic really.
And apologies, I misread your last post - I thought you were saying it'd be cheaper to rebuild the plant.
To bring this crashing back to the main issue at hand: Unit 4 is now on fire. Radius has been extended to 30Km from 20Km.
I'll try and link it to an article as soon as I can find something in English.
EDIT: initial google hit -
http://atomicpowerreview.blogspot.co...ichi-no-4.html
All I can find are blogs and tweets in English, though no doubt the BBC will be running it live on TV or something...
Looks like one of the Japanese air force bases was also hit by the tsunamic with 18 F2 fighers damaged or destroyed:
http://www.flightglobal.com/blogs/th...-japan-f-.html
http://www.jutjub.net/movie.php/XBGF...20Force%20base
That is nearly 2 billion dollars of planes!!
There seems to be live updates on this web-page:
http://www.guardian.co.uk/world/2011...s-tsunami-live
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