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First, it doesn't say that the backup generator did not work. An oil leak doesn't mean the system will not function. It's something to pay attention and repair,

First, it doesn't say that the backup generator did not work. An oil leak doesn't mean the system will not function. It's something to pay attention and repair, but not something critical. If your car has an oil leak you keep driving it and repair it when you have time to do so. Second, the diesel generator is just one of many backup systems. To use it you have to have the (at least) two independent connections with the grid fail. Even if it does, you don't have one generator, but more than one. Even if the generator fails, passive system will cool down the reactor for a couple of hours, enough for a mobile generator on a truck to arrive and be connected, without any damage. There were only one case where generators and all external power supplies had failed, that is of course Fukushima. Even in that context, if the passive systems where not damaged by the tzunami, there wouldn't have been any release of radioactivity. And even in that context, considering that the containment had design flaws, the impact on the environment wasn't that huge. That is, nuclear power plants have multiple systems that can fail, as a complex machine. The fact that one system fails or has some issue doesn't necessary mean that the safety of the whole power plant is compromised.

dale_glass 3y ago
> An oil leak doesn't mean the system will not function. If oil runs out, then the generator will very much stop functioning, in an ugly and hard to fix manner. Something you very much don't want in an emergency. > It's something to pay attention and repair, but not something critical. Sure, the thing making sure the reactor doesn't suffer catastrophic damage is not critical. Right. I also must have forgotten that disasters politely add themselves to the schedule with plenty warning time. > Even if the generator fails, passive system will cool down the reactor for a couple of hours, enough for a mobile generator on a truck to arrive and be connected, without any damage. Didn't quite work that way for Fukushima. > There were only one case where generators and all external power supplies had failed, that is of course Fukushima. Even in that context, if the passive systems where not damaged by the tzunami, there wouldn't have been any release of radioactivity. Sure, it only took lots of people working around the clock to keep things contained (so it seems it wasn't something one could just ignore, it needed urgent work), and it cost a huge amount of $$$ to deal with it, and it destroyed those reactors, which is more $$$. That it didn't blow up Chernobyl style is absolutely a great thing, but it probably cost more than it ever made money, and that's not exactly something that encourages anyone to build more.
crote 3y ago
They found cracks in fuel oil lines. Last time I checked, generators need fuel to operate. In fact, the article even states: > the problem grew to a point where the diesel generator system did not work during testing. You have backups because things unexpectedly fail. It's the Swiss Cheese model: more than one system can fail at the same time so you should be able to handle multiple failures at once. Especially because failures often cause other failures to happen. Fukushima also had multiple grid connections. They had 13 emergency generators which could be cross-connected between reactors. They could also bring in mobile generators. It still wasn't enough, because they shared a huge unknown common failure mode. Fukushima is exactly the reason why ignoring defects on one of your two emergency generators for twenty years is such a big deal. When the potential impact is as large as it is with nuclear power, you simply cannot afford slacking off like this.
cycomanic 3y ago
I sure hope you don't make safety critical decisions. If you look at the history of failures in modern complex systems you almost always see that it happens as a series of unlikely events (or events that someone deemed impossible), that let to catastrophic failure. That's the whole point of multiple safety mechanisms, have backups in case one fails. If you start removing the backup mechanisms (e.g. through improper maintanance like it is the case here) you reduce the overall safety of the system. Does that mean certain catastrophic failure in case the system is needed? Probably not, but it increases the likelyhood of a chain of events that lead to it. The main news here is not that they had cracks in the pipes, the main news is that over the last 20 odd years the operator never bothered to do a proper fix instead opting for the (likely cheaper) quick fix.

dale_glass 3y ago

> An oil leak doesn't mean the system will not function. If oil runs out, then the generator will very much stop functioning, in an ugly and hard to fix manner. Something you very much don't want in an emergency. > It's something to pay attention and repair, but not something critical. Sure, the thing making sure the reactor doesn't suffer catastrophic damage is not critical. Right. I also must have forgotten that disasters politely add themselves to the schedule with plenty warning time. > Even if the generator fails, passive system will cool down the reactor for a couple of hours, enough for a mobile generator on a truck to arrive and be connected, without any damage. Didn't quite work that way for Fukushima. > There were only one case where generators and all external power supplies had failed, that is of course Fukushima. Even in that context, if the passive systems where not damaged by the tzunami, there wouldn't have been any release of radioactivity. Sure, it only took lots of people working around the clock to keep things contained (so it seems it wasn't something one could just ignore, it needed urgent work), and it cost a huge amount of $$$ to deal with it, and it destroyed those reactors, which is more $$$. That it didn't blow up Chernobyl style is absolutely a great thing, but it probably cost more than it ever made money, and that's not exactly something that encourages anyone to build more.

crote 3y ago

They found cracks in fuel oil lines. Last time I checked, generators need fuel to operate. In fact, the article even states: > the problem grew to a point where the diesel generator system did not work during testing. You have backups because things unexpectedly fail. It's the Swiss Cheese model: more than one system can fail at the same time so you should be able to handle multiple failures at once. Especially because failures often cause other failures to happen. Fukushima also had multiple grid connections. They had 13 emergency generators which could be cross-connected between reactors. They could also bring in mobile generators. It still wasn't enough, because they shared a huge unknown common failure mode. Fukushima is exactly the reason why ignoring defects on one of your two emergency generators for twenty years is such a big deal. When the potential impact is as large as it is with nuclear power, you simply cannot afford slacking off like this.

cycomanic 3y ago

I sure hope you don't make safety critical decisions. If you look at the history of failures in modern complex systems you almost always see that it happens as a series of unlikely events (or events that someone deemed impossible), that let to catastrophic failure. That's the whole point of multiple safety mechanisms, have backups in case one fails. If you start removing the backup mechanisms (e.g. through improper maintanance like it is the case here) you reduce the overall safety of the system. Does that mean certain catastrophic failure in case the system is needed? Probably not, but it increases the likelyhood of a chain of events that lead to it. The main news here is not that they had cracks in the pipes, the main news is that over the last 20 odd years the operator never bothered to do a proper fix instead opting for the (likely cheaper) quick fix.