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Originally Posted by JohnnyD
If you're really interested, compare the environmental impact, loss of life, energy costs and generated energy per acre of things like oil, coal, NG and you'll see that nuclear is still a winner by far.
Don't get me wrong, there is definitely a very long-term effect when there are incidents but 3-4 incidents out of the hundreds of plants over 30 years is far from a convincing argument - especially considering what current designs require as safety measures. Taking the environmental aspects out - coal, oil and NG won't be here forever.
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And consider that TMI and Chernobyl were major human errors whereas Japan's problem was a quake 100 times greater than thought possible there FOLLOWED by a Tsunami 30% higher (and far more powerful) than expected. Two items deisnged for but independently of the other (also consider that the Japanese Nuke engineers didn't have lights in the control room until 2 days ago but I digress).
Modern systems are supposed to be much better and designed to automatically shut themselves down in blackout conditions where there is no power to run the systems - not the same as these designed 40 years ago (TMI and Fuk). Chernobyl design is supposed to be the worst plant design you could ever do, even by Soviet standards. A nuclear dirty bomb WITHOUT any kind of containment.
Fuk's problem was from what I read a cascade of worst case scenarios taking place one after another;
- Quake hits, Reactors shutdown by design (takes months to cool all the way down but a long as cooled they cannot go critical). They would have failed over to regional power supplied by one of several local non nuke plants nearby but those were damaged so much as to be offline. Redundant system 1 failed.
- The system then failed over as designed to backup diesel generators (BDGs). Redundant system 2.
- Tsunami wipes out BDGs 30 minutes later, system fails over to Redundant system 3 battery backup with 8 hour plus capacities even with extensive facility damage (look at the before / after pics).
- Battery backups fail after a day. Redundant system 3 failed.
- BDGs restarted (Redundant system 2) but fuel is fouled by Tsunami damage (our BDG fuel storage is supposedly very difficult to damage and also has multiple ways to route to system - redundancy to redundancy). Redundant system 3 failed.
- Explosions of venting Hydrogen from reactor vessels into unventilated area (supposedly our plants of this design were back fit many years ago to allow venting to occur and not have explosive gases contained in outer building).
- Additional BDGs flown in but either incompatible by design AND/OR connections not accessible within buildings damaged by explosions. Well beyond redundant systems now and trying to MacGiver 8 reactor plants.
It is amazing they have not had worse failures to date since the quake.
Also from what I have read, the recent designs are set to naturally cool in blackout conditions like what hit the Fuk plants multiple times. So while they will have Redundant system on Redundant system, the design of the plant will from the get go cool itself even without power.
Hybrid Mode
