Nuclear power

Niv

macaque wrote: »

As a matter of interest, if a nuclear power plant was planned to be located one mile from your house, would you object?

No, I would not and am not. There are plans to install a new reactor near me and the public consultation is underawy. Okay a little over 1 mile away but close enough for your point and I knew about the place before I bought my house.

Nik - you said that you were coming around to nuclear then this has put you off. When do you expect the UK to be hit with a 8.9 earthquake followed by a tsunami? Put things into perspective, I agree nuclear stations may not be suitable in every location on the planet but just because a plant on a fault line that has been hit by a massive earthquake and tsunami is having some issues does not mean that they are unsuitable everywhere.

ninky_2

reports now saying the 'spent' stored rods might rereach criticality again. they are considering spraying with boric acid to prevent. desperate measures.

Arcaine

1984ReturnsForReal wrote: »

Good post. I suppose they tested reactors rigorously also.


Anyway, you see that big crack that starts in Fort William & runs all the way to Inverness (well, I am sure it runs further but under the sea)?

http://maps.google.co.uk/maps?hl=en&client=firefox-a&rls=org.mozilla:en-US:official&q=map+of+scotland+fault+line+fort+william+to+inverness&um=1&ie=UTF-8&sa=N&tab=wl

That "Big Crack" is called the Great Glen Fault, it is estimated to be around 430 million years old and was formed during the end of the Caledonian orogeny (period of mountain building) where Scotland was covered in mountains as high as the Himalayas and is what is called a strike-slip fault, ie. the movement was horizontal rather than vertical. The displacement distance ranges along the fault, but is around 50-70 miles. It has moved at various times during its history but the last was around 60 million years ago.

As with all faults they can move when areas become active again. But faults not in active areas tend to be stable, even so minor earthquakes can and do happen, up to about 4 on the richtor scale. The kind we get occasionally in the UK.

Yay, finally a use for my Geology degree. I admit though I had to look this up in my old notes.

Edit : I am no geological engineer, but Japan is one of the most Geologicaly active areas in the world, it is not only on a plate subduction zone which produces the worlds largest earthquakes (all of the worlds largest earthquakes are termed Mega thrust earthquakes and are associated with plate subduction zones). It is also close to the meeting point of 4 separate plates of the earths crust. Any type of infrastructure needs to be very resiliant to these kind of events. I just wonder how nuclear engineers, Geologists and Government could justify putting over 30 nuclear reactors into this kind area.

ninky_2

Arcaine wrote: »

Edit : I am no geological engineer, but Japan is one of the most Geologicaly active areas in the world, it is not only on a plate subduction zone which produces the worlds largest earthquakes (all of the worlds largest earthquakes are termed Mega thrust earthquakes and are associated with plate subduction zones). It is also close to the meeting point of 4 separate plates of the earths crust. Any type of infrastructure needs to be very resiliant to these kind of events. I just wonder how nuclear engineers, Geologists and Government could justify putting over 30 nuclear reactors into this kind area.

nz is similarly very active but also rejects both nuclear power and weapons.

these are the same nuclear engineers, regulators etc whom we are now supposed to trust when they say modern power stations are 100 percent safe and all eventualities have been considered.

irok20002

Arcaine wrote: »

That "Big Crack" is called the Great Glen Fault, it is estimated to be around 430 million years old and was formed during the end of the Caledonian orogeny (period of mountain building) where Scotland was covered in mountains as high as the Himalayas and is what is called a strike-slip fault, ie. the movement was horizontal rather than vertical. The displacement distance ranges along the fault, but is around 50-70 miles. It has moved at various times during its history but the last was around 60 million years ago.

As with all faults they can move when areas become active again. But faults not in active areas tend to be stable, even so minor earthquakes can and do happen, up to about 4 on the richtor scale. The kind we get occasionally in the UK.

Yay, finally a use for my Geology degree. I admit though I had to look this up in my old notes.

Edit : I am no geological engineer, but Japan is one of the most Geologicaly active areas in the world, it is not only on a plate subduction zone which produces the worlds largest earthquakes (all of the worlds largest earthquakes are termed Mega thrust earthquakes and are associated with plate subduction zones). It is also close to the meeting point of 4 separate plates of the earths crust. Any type of infrastructure needs to be very resiliant to these kind of events. I just wonder how nuclear engineers, Geologists and Government could justify putting over 30 nuclear reactors into this kind area.

Its worth noting that the 8.9 earthquake that for some reason this specific plant wasn't designed against (newer ones are) didn't even affect the plant, and the it was the tsunami which was also far bigger that it was designed against that took out the backups not the plan itself. The plant should have been protected against this and it could have been.
You seem to be lumping all nuclear reactors into your statement when infact it should only be this specific design.

Arcaine

I really dont have much of a clue on construction of Nuclear reactors. I was just wondering what they did consider to be safe tolerances/backups when these were built, considering the events that these plants could potentially be subjected too. (When I said event I do mean Earthquake generated Tsunami as well.)

ninky_2

irok20002 wrote: »

Its worth noting that the 8.9 earthquake that for some reason this specific plant wasn't designed against (newer ones are) didn't even affect the plant, and the it was the tsunami which was also far bigger that it was designed against that took out the backups not the plan itself. The plant should have been protected against this and it could have been.
You seem to be lumping all nuclear reactors into your statement when infact it should only be this specific design.

but i've seen nothing to convince that newer designs could have dealt with this situation either.

i don't think anything can stand up to a 9.0 earthquake and related tsunami 100 percent....maybe if the coolant delivery system is underground? but then that could still be damaged by a quake and would be harder to fix if a problem did occur.

for example what happens if the coolant (water) supply runs out or is blocked? protecting the coolant system is a vital a protecting the fuel itself because if it stops working there is no material that can contain nuclear fuel at the temperatures it can reach afaik.

i'd like nothing better than to be proved wrong. it would be great if the safety features were convincing. there needs to be an open dialogue on this and for people to come up with all conceivable situations and how they would be protected against.

irok20002

Modern nuclear power plants in the UK have to be able to withstand whats considered a 1 in 10 000 year event, the tsunami was considered a 1 in 1000 year event so should have been covered, though it is a 40 year old plant, its coming out now that many concerns had already been raised.

The level of safety imposed on new build nuclear power plants is immense, if coal or oil plants had to provide that level of safety (impact on people's health) they would all be shut down tomorrow as they would not be cost effective.

Its clear that these measures were no imposed on Japans old fleet however. The plant still nearly survived though. I'm not defending it though, this is a big mess, only more modern plants or even ones built at the same time but to the required safety standards.


Its interesting no one seems to be complaining about the massive amounts of carcinogens being thrown into the atmosphere by the burning oil depots, at a much higher risk to health to the general population than the radiation confined to just around the nuclear plant.

Degenerate

ninky wrote: »

but i've seen nothing to convince that newer designs could have dealt with this situation either.

That's because you're not interested in learning anything outside your narrow preconception of nuclear power. The problem here is that the ancillary systems did not stand up to the quake & tsunami, not the reactor itself. Passive safety designs that don't require such systems to remain safe have already been mentioned, educate yourself.

ninky_2

Degenerate wrote: »

That's because you're not interested in learning anything outside your narrow preconception of nuclear power. The problem here is that the ancillary systems did not stand up to the quake & tsunami, not the reactor itself. Passive safety designs that don't require such systems to remain safe have already been mentioned, educate yourself.

the japan plants already used elements of 'passive safety' - i understand it's a broad description and therefore of itself it's not particularly helpful. i think what needs to be put forward is the specific design of any plants being proposed so that broad scientific opinion could be sought and judgements made (although possibly that could be considered some sort of terrorist threat i think openness is really the only was forward).

i don't think passive safety as a concept of itself is enough to reassure people at this stage.

IAEA explicitly uses the following caveat:

... passivity is not synonymous with reliability or availability, even less with assured adequacy of the safety feature, though several factors potentially adverse to performance can be more easily counteracted through passive design (public perception). On the other hand active designs employing variable controls permit much more precise accomplishment of safety functions; this may be particularly desirable under accident management conditions.

i am actually interested in learning. very much so. i think the science is fascinating. what i'm not keen on is handing over the decision making to a narrow group of industry paid henchmen (scientific or otherwise).