How does a nuclear power plant work?
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Let me give my take on this. Most atoms are made up of 3 parts.
Protons – these literally define what an atom is. If it has 2, it’s helium. If it has 6, it’s carbon. They’re also positively charged, so they like to push away from each other, just like if you push two positive sides of a magnet together. These live in the middle of an atom.
Neutrons – these guys sit with protons in the middle, and are about as heavy as a proton, but have no charge. They can help stick between protons to make them push apart less, and when you add or subtract them, it can shift up the structure of the center. This can make an atom more or less stable, because of those protons pushing against each other. Every atom has a most stable number. If an atom has a different number of neutrons, it is an *isotope* of that atom. One of the most famous isotopes is U-235, or a Uranium atom with 235 neutrons. It is pretty unstable, with all that energy in it, barely held together.
Electron – these are super light and super fast, and fly around outside the edge of an atom. These have a negative charge. If an atom has more or less of these, it is an *ion*. These aren’t terribly relevant for nuclear reactions, though they’re talked about when you talk about multiple atoms hooking together into molecules.
So if you get these unstable isotopes, they want to break apart, they just need something to start it off. That something is usually a very fast neutron smashing into it. When that happens, all hell breaks loose. The center breaks into 2 lighter pieces with some protons and some of the neutrons. And 2 or 3 neutrons go flying off, super fast.
If Uranium-235 is enriched enough (there’s enough uranium-235 in there, and less of other uranium isotopes), those 2 or 3 neutrons will smash into other uranium atoms, breaking them, which makes more neutrons, and keeps chaining together. If this goes too fast, you can add something to soak up neutrons, to slow the reaction down. In reactors, that is a Control Rod.
Over time, we get the uranium turned mostly into other elements. But when they split, it releases a LOT of energy. As an example, there was about 10 pounds of plutonium in the bomb dropped on Nagasaki in World War 2. It released as much energy as 42,000,000 pounds of dynamite (21 kilotons). Something about the weight of a bowling ball released as much energy as millions of pounds of high explosives.
But slowed down, and controlled, that can provide a stable, reliable, and long lasting heat source that can boil water to produce electricity in much the same way that any other plant does.
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