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Comment by Zealotux | Hacker News Reader

When you take into account he amount of energy that has been produced by nuclear power since the 50s, I'd say we have a pretty good record when it comes to overall safety.

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I agree with most of your points, however: most of the accidents have more to do with flaws in regulations than mistakes from the nuclear engineers. Chernobyl, which is arguably the worst and most iconic nuclear disaster of all times was mostly caused by a severe violation of procedures. When you take into account he amount of energy that has been produced by nuclear power since the 50s, I'd say we have a pretty good record when it comes to overall safety.

The biggest problem with Chernobyl was the reactor design, which had a positive void coefficient, which outside of something like CANDU reactors is considered insane today. It’s true that their experiment with simulated blackout was the proximal cause, but the fact that increased steam production led to higher power output was the big factor that made it such a huge disaster.

When I learned about Chernobyl reactor, I was surprised how bad the design decisions were. Casing the reactor core in wooden housing?

IIRC the control rods were also bizarre and had graphite bottoms, so the first part of a trip (scram) was adding reactivity.

Prompt critical is prompt.

I believe the rods were graphite, just like the moderators. Of course the problem with that was that by the time they were inserted the reactor was already out of control. All the graphite rods did was burn, which certainly didn’t help matters! Worse, after a while the blocks of graphite used as the moderator also burned, and was difficult to extinguish. What they needed (other than better reactor design) was a ready store of neutron poisons that would have flooded the reactor vessel before rod insertion. Unfortunately, by the time they were using neutron poisons the explosion and fire had already destroyed anything like containment.

Chernobyl didn't have a containment or shield building. Manually disabling the safety systems didn't help.

The control rods had a plug of graphite on their ends, I believe, which made reactivity briefly increase as they were first inserted.

Chernobyl was a "military reactor", ie. could produce plutonium. Normal reactors don't even have the same failure mode possible. So you can blame the accident on the cold war or something, not nuclear in general.

http://www.phyast.pitt.edu/~blc/book/chapter7.html

also not helped by the fact that recent plant construction wasn't superbly handled.. delay, additional cost, failure of quality control for main parts..

Sadly I think nuclear energy needs a branding motive. Something that pushes everybody to make it clear, fast, precise and shiny. To instill trust in the eyes of people (that would require 10 years to educate on the physics)

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