How exactly does nuclear power plants work? How are they able to generate electricity using radioactive things?


How exactly does nuclear power plants work? How are they able to generate electricity using radioactive things?

In: Physics

Nuclear decay produces heat. They use this heat to boil water and drive a turbine with the steam. The turbine is hooked up to a generator and, tadah, electricity.

The radio active rods generate enough heat to boil water. Which in turn makes steam to turn their turbines that generate electricity. Layman’s explanation.

Radioactive material produces heat which is used to heat up water. The steam is then used to turn a turbine that is connected to a generator. Afterwards the steam is cooled down again and goes back into the reactor to be heated up again.

Radioactivity heats up the material as it decays. The water that cools the reactor absorbs that heat in two ways, directly by contact with the fuel rods, but also by catching the neutrons that the decay sends flying. (Moderate the radioactive decay with control rods so it doesn’t overheat)

So you have hot water, send that through a heat exchanger to evaporate water in a second cycle. Send that steam through a turbine that spins a generator to make electricity.

It’s basically the same like a coal powerplants only that the source of the heat is different.

A second way is the radionucleid battery wich generates electricity more directly using a thermoelement (works similar to photovoltaic cells but with heat)

Oh man, I feel particularly qualified to answer this question. I was a licensed reactor operator at a nuclear plant for eight years.

Most large power plants use steam to push a turbine (a type of windmill-in-a-box) that is attached to an electrical generator. To make the steam, they heat up water.

Where does the heat come from? Ah, that’s the interesting part. In a coal-fired or natural gas power plant, the heat comes from combustion (burning) of the fuel. But with a nuclear power plant, the heat comes from fission.

What is fission? It’s the splitting of a big atom (usually Uranium) into two smaller atoms. The reactor vessel is the container in which the fuel is fissioned. Cold (well, relatively cold) water goes into the reactor and comes out hot.

Nuclear reactions heat water that produces pressure in an engine that produces energy, electricity.

That’s as simple is gets I believe. Just remember that the electricity is not made directly from the nuclear power, that’s the normal misunderstanding

In a reactor core you have three major components, nuclear fuel, a moderator and coolant each of these have an important par to play.

The fuel is the source of all your energy most reactors have two parts to their fuel. One of these is mostly stable the other isn’t the unstable atoms will break apart and release radiation this is called decay. this releases different types of radiation but the one we need to focus on is neutron radiation. when our unstable atoms come apart neutrons are launched at nearly light speed. we want these neutrons to hit our stable atoms to make them break apart and release more neutrons, this the react in reactor.

These neutrons at light speed aren’t going to break apart our stable atoms so easily, first we need to slow them down. This is where our moderator comes into play. Imagine you shoot a bullet going 20x the speed of sound at a car, its probably going to create a small hole and pass strait through. Something similar happens to our atoms (albeit in a very different way). When the neutrons in our reactor hit our moderator they will bounce off it and the moderator will slow the neutron from the speed of light to about the sped of sound, this is what will be able to break apart our stable atom.

Wait but how does this produce electricity? well when each of our atoms comes apart it releases energy, and quite a bit of it a that in the form of heat. and this is the job of our coolant. although movies might say otherwise coolant is actually hot, because it needs to ferry all this heat produced in the reactor away. different reactors use different coolants but they all boil down to water in the end. when we heat up water it turns into steam and quite a bit of it can be produced form a reactor, we can then use this steam so spin a turbine a bit similar to one that the back end of a jet engine. this turbine then spins a dynamo which generates electricity.

Nuclear power plants are glorified Steam power plant. Water is vaporized by applying heat. Source of heat can be many things.

Radioactive things can go under “chain reaction”. The reaction is continuous and heat is released. Then the heat is used to produce steam and run generators using turbines.

There is orders of magnitude more energy in nuclear fission than in e.g. burning coal. Energy that will be released mostly as heat. A WHOLE LOT of heat. This heat boils water in a pressurized system which makes it become very pressurized steam that is, like in all fossil power plants, used to drive a turbine coupled to a generator.

The principle is the same as in coal plants, but it’s also way more difficult to control an ongoing nuclear fission without releasing too much energy at once, but also not choking it off. There’s actually a very narrow window of how much fisisons per time is safe and stable to handle. It’s like slowly riding a rocket through a school zone.

* Most electricity is made by turning a thing that has magnets.
* Most of those magnet machines are turned by forcing steam through a thing.
* Most of that steam is made by burning something.
* However, putting enough of certain radioactive elements together allows them to smash apart which releases a lot of heat.
* So nuclear plants use that instead of burning something.

The Naval Nuclear Power ELI5 is:
Hot rock make steam
Steam make roundy-roundy
Roundy-roundy make sparky-sparky

Poke uranium in just the right way, it gets real hot. Use that heat to boil water, voilá reverse kettle