How do nuclear powered submarines work? Are they the same as nuclear power plants? Where does the waste go?
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They swap out spent fuel just like a bigger reactor. It’s sent into storage or to a reprocessing plant. And yes, quite similar to land based plants just more compact
After fuel rods are used up, they’re offloaded and replaced with new fuel while in port.
Ironically, knowing how dangerous waste disposal is in the US, it probably ends up dumped in the ocean anyway.
They are the same as a nuclear powerplant in a very basic concept level – radioactive fuel makes hot water and we extract the heat from the hot water to do stuff. The exact plants and nuances of how they function are varied, but it’s the same rough concept.
They don’t really produce much waste, actually I believe the current generation of nuclear plants will last *longer* than the submarine they are built into. So it’s a sort of fuel it up once and it’s good to go until you dismantle the ship sort of thing.
They do produce waste heat and yes, you can theoretically use satellites to look for trails of water that’s warmer than it should be to find subs close to the surface.
Pretty much the same, just on a smaller scale. Nuclear fuel heats water into steam, steam turns turbine and makes lightning, lightning turns the screws.
The reactors used on naval vessels are very small and efficient, relatively little waste is produced. Waste is removed during refueling every 25 years or so, stored with all the rest of it under Yucca Mountain.
In general, nuclear power systems don’t actually produce much waste material.
They periodically get their fuel swapped out, but that’s a good 20 – 30 years of service-life before that needs to happen.
Most nuclear waste is actually just irradiated material, things like hazmat suits, tools used to handle radioactive materials, misc debris.
Trash really. Very little is actual plutonium/uranium or anything like that.
Beyond that, a nuclear submarine’s reactor functions very much the same as a larger land-based reactor.
Radioactive material gets hotter the closer you pack it with more of itself, and you can use that heat to boil water into steam and drive turbines to generate electricity.
Basically some kinds of atom are ridiculously overcomplicated and will shed bits of themselves steadily until they reach a stable state. This can take thousands of years to finish.
These offcast neutrons don’t just disappear though, they fly off with some force and smack into other atoms and break them up in turn, producing more neutrons which smack into more atoms etc etc.
The tighter-packed the radioactive material, the faster this happens.
All of this breaking of atoms produces a lot of extra energy which manifests as heat.
So if you get a big pile of uranium, it will heat up. Do it right, it can boil water, which produces steam, which drives turbines, generates electricity and powers your submarine.
As a side-note:
The basic operation of a nuclear bomb is to pack the radioactive material as close together as possible and make the atoms pop as quickly as possible for maximum heat.
This is generally accomplished by use of conventional explosives to squeeze the uranium together, plus various extra stuff like Berylium lenses to produce additional neutrons to get a more thorough atom-popping.
Do it all at once and you get a lot of energy, and that’s gotta go somewhere. Generally it goes into a very large explosion.
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