How does a nuclear power plant work?
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There’s a few minerals that decay slowly over hundreds of thousands of years, producing about a million times as much heat as burning the same amount of coal. One such mineral that’s particularly famous is called pitchblende. The property of undergoing that sort of decay is called radioactivity.
Radioactivity is mostly useless on its own because the heat release is too slow to do anything with. But we’ve found particular ways of purifying certain radioactive minerals and arranging them in special shapes so the bits of material that are currently decaying interact with the rest of the material and speed up its decay. In a nuclear power plant, a purified product derived from pitchblende is arranged so it decays rapidly and gets hot, and the heat is used to boil water. The steam from the boiling water is directed into windmill-like structures called turbines, which spin and generate electricity.
Certain materials are considered fisile. That’s the technical term for materials that are made out of unstable atoms. The atoms in nuclear fuel are large and don’t hold together well. They tend to split into smaller atoms along with some spare parts. Those spare parts sometimes hit other atoms, making them more likely to split as well. When atoms split, they release the energy that was holding them together in the form of heat. We can capture that heat by immersing rods of nuclear fuel in water and letting that water boil. From that point on, a nuclear power plant doesn’t operate in any significant way from a coal or gas burning power plant. High presure steam from the boiling water forces turbines to spin, and those turbines are attached to dynamos, which use the motion magnets and coils of wire to create electric current.
In a giant pool of water, self-heating rocks are placed next to other self-heating rocks, which heat each other up even more. These also heat the surrounding water into steam. The steam is piped away to drive an enclosed fan that turns a generator which produces electricity.
They generate a lot of heat, which turns water into steam, which is then used to spin a turbine that produces electricity.
It works exactly like a coal of natural gas fired powered plant. Instead of coal or natural gas they split atoms to create the heat to produce steam to turn of generator.
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.
When you think about it it’s a very simple process at how nuclear power works.
First you have a core. Which is a giant cement shaped bathtub filled with water. In this water are “fuel rods” and “control rods” when you life the control rods? The fuel rods heat the water causing it to boil.
The steam from the boiled water turns a turbine which is connected to a dynamo. The dynamo turns and that’s how electricity is made
It works like putting a pin wheel next to a steaming tea kettle. The steam causes the pin wheel to spin. In a nuclear power plant, the spinning pin wheel is a generator, and nuclear material is what heats the tea kettle (reactor).
It depends a bit on the fuel and exact reactor design, but the basics are:
* Rods of refined fissile material (usually Uranium) in a fluid medium are allowed to get close enough to each other that the radiation they naturally emit begins a sustained fission reaction. An atom splits (fissions) and fires off extra neutrons and sometimes protons, as well as releasing a fair bit of extra energy. The particles it fires off when it splits hit additional atoms and split those, in a chain reaction.
* Control rods of some neutron-absorbent material are interspersed with the reactor rods to absorb some of the excess neutrons. Rods can be added or removed to control the speed of the fission reaction, so that it can be sustained without getting out of control and making the reactor too hot.
* The energy released by the reaction heats the core. Outside the core is another layer of fluid that absorbs the reaction heat. This fluid is heated enough that the pressure can be used to drive a turbine (usually as steam). The turbine produces electrical power. It’s important to note that the fluid turning the turbine typically has no direct contact with the radioactive material in the core.
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