Japan's Nuclear Problem

looked good. There were no major problems. The reactor hadn't cracked or you know, fallen over anything because of the earthquake, and it looked really good. But then by Saturday, things had taken a turn for the worst, so there were reactor buildings exploding. There was all kinds of talk about meltdowns and China syndrome and all this other stuff. So when you think about it, a nuclear power plant is supposed us to be one of the most amazingly engineered,

super wonderful things in the world. With umpteen levels of redundancy, and every single contingency thought about and poured over and inspected both nationally and internationally, there should have been nothing that could go wrong in Japan's nuclear power plants, and yet it did. So what happened and how did things go from being really quite stable to completely unstable and leading to some of the worst nuclear accidents ever to

occur on the planet. So let's take a look at what happened step by step, because it really is an interesting story and it shows how even when something is engineered to the highest levels and given multiple layers of redundancy and so on, things can still go sour. In step one, the earthquake happened, and this was fine. The four reactors that were nearest the epicenter of the earthquake detected the earthquake and they shut down automatic, just like

they were supposed to. So what does shut down mean? If you were to look inside these nuclear reactors, you would see fuel rods filled with nuclear fuel little pellets about the size of your little finger that are arranged in these rods and collected together in bundles, and the control rods moved down between the rods to absorb neutrons that are coming out of the uranium atoms in the fuel. And once you absorb the neutrons, you basically quench or

stop the nuclear reaction. That's creating the heat that's creating the steam that's creating the electricity for the power plant. So they automatically shut down the control rods moved into the reactor core, absorbed all the neutrons quen the reaction. Now there's still some, well not some, a lot of residual heat in that reactor core, both from other radioactive elements of short life that are in the core before it's quenched, and also just the heat that had accumulated.

You can't have a gigawatt power plant with you know, a light bulb as that. Here, you have a giant mass of something that's hot and it's it's itself is going to take time to cool down. So the earthquake happened, nothing happened to the buildings. They were engineered properly and and sustained no damage in the earthquake. The reactors shut down and everything was fine. So now you have these big nuclear reactors which are in the process of cooling down,

which is gonna take some time. And during that cooling down process you need to circulate cooling water through the cores. Unfortunately, the power grid wasn't in such great shape and so power failed to the nuclear power plants, and you would think this wouldn't be the big problem, since they are power plants after all, but they had been shut down automatically,

so they aren't producing electricity. So in this situation where your nuclear power plant is shut down and you have lost the connection to the power grid, what they've got is on site backup diesel generators. So these diesel generators fired up to provide power that would run the pumps that would keep these cores cool. That system worked properly

and everything was fine until the tsunami hit. And normally a tsunami hitting a nuclear power plant wouldn't be a big deal because they know about tsunamis and had designed against them. But they had not expected this big of a tsunami, so when it hit, it basically inundated the diesel generators, all of them, and took them out of service.

Now you could argue that the engineers should have put the diesel generators up higher so they couldn't have gotten hit by a tsunami, or they should have made the diesel generators submersible so even if the tsunami came, they could run submerged and keep power going. But neither of

those things happened, so the diesel generators failed. Now, in a nuclear power plant, there's another backup system which involve alves batteries, and batteries are there in case the diesel generators fail so that you have time to get some kind of additional backup plan in place. But these are batteries. Think about how batteries are in your life. They're always going dead, they never last long enough. If they're fully charged,

you're you're still subconsciously thinking about them going dead. And batteries at a nuclear power plant are no different. These were designed to have a lifespan of about eight hours. So the batteries are circulating cooling water through the cores and everything's fine, And meanwhile the engineers are trucking in backup backup diesel generators to puck into the nuclear power plants and fire them up. But when these when these backup backup generators arrived, apparently they had the wrong plugs

on them. They weren't quite compatible with the nuclear power plant, according to some reports, and they couldn't just be hooked

in instantly, which meant that the batteries went dead. And this is where things started to come unraveled without cooling water circulating through the core, the reactor core starts to heat up and it starts to boil the cooling water, and as that water boils off, it starts to lower the level of water in the reactor core, causing some of the clear fuel rods to not be submerged in

water anymore. At this point, the fuel rods overheated and cracked, allowing water to get into the very very hot nuclear pellets and you get dissociation of the water molecules and the production of hydrogen. It builds up in pressure and it has to be vented off, and that normally wouldn't be a problem. Factories vent gases all the time, but for some reason, when they vented off a large quantity of hydrogen gas, it ignited and exploded, and this caused

the building around the reactor vessel to disintegrate. Basically, the whole top of it was blown off by the hydrogen explosion. And this occurred multiple times, apparently at multiple plants. Now, if this process had been allowed to continue, the process of boiling the cooling water off and exposing more and more of the core, things would have gone from bad to worse because eventually the nuclear fuel pellets would get so hot that they would melt. And this is where

the word meltdown comes from. The idea that the nuclear fuel heats up, melts and becomes what one article termed radioactive lava that flows to the bottom of the reactor vessel and potentially each through it and ends up in the floor of the reactor containment building. To prevent that from happening. To prevent a meltdown, the technicians in Japan

decided to start pumping seawater into the reactors. And this is largely a desperation measure because the seawater ruins the reactor and you're not ever going to be able to to fix it. You're gonna have to scrap the whole thing and start over. So they start pumping seawater in

and that prevents a meltdown. Long term, that's going to have some serious consequences for the whole nuclear industry in Japan and for the Japanese Power Group, because nuclear power is an important part of the power system in Japan. It makes up you know, these failed reactors make up something like fifteen percent of the whole electricity generating capacity of the country and that's a big loss for a country to sustain and will have to be replaced both

short term and long term. So what does this whole episode mean in real terms? That depends on how you want to spin it. So if you don't like nuclear power, the way you spin this is you say, look, these terrible things happened. These were supposed to be well engineered systems, but clearly they were not. There was radiation that was released into the environment, there were explosions, there could have been a meltdown. Things just did not go as we

were are told they were go. Would go in an engineer system like this, Nuclear power should not be allowed anywhere on the planet. If you're pro nuclear, you'd spin it the other way. You'd say, well, these reactors were designed and engineered with redundant systems and with procedures to handle just about any possible scenarios. So a lot of stuff went wrong, and yet in the big picture, nothing

seriously dangerous happened as a result of the problems that occurred. So, yes, a little bit of radiation was leaked into the atmosphere, but most of it is harmless, very short lived, and that which wasn't completely harmless happened to blow out to see, so it wasn't affecting any major population areas or anything like that. And there were no meltdowns and there were no you know, radioactive explosions like we had at Chernobyl,

So nothing really bad happened. And even if the meltdown had occurred, it would have been okay because it would have been contained within the containment build thing and it wouldn't have been any big deal. You can kind of pick how you want to personally spend this event, whether you want to be pro nuclear or anti nuclear, or somewhere in between. Be sure to check out our new

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