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Mhgglmmr t1_iulj17w wrote

Reply to comment by TheNoobsauce1337 in Engineering question: With today's material sciences, why don't ocean liners use pressurized steam to power electric engines? by [deleted]

If you have enough electrical power on board already (generated by what exactly?), why would you use that to generate steam to power a turbine to turn generator to generate electricity for an electric motor? Just run the electric motor directly.

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TheNoobsauce1337 t1_iulk00d wrote

This is my thought process:

Pre-charged startup batteries to begin boiling process with water brought in from the ocean.

Water begins to boil and is replenished from the ocean periodically.

Steam held at high pressure turns generators that sustain a constant flow of power.

Constant flow of power powers electric engines, boilers and backup batteries. Also recharges startup batteries in case the entire system needs to be restarted.

Engine and boilers relies primarily on generators at this point, which rely on periodic refills from the ocean (though battery backups are installed if something fails).

Basically a self-sustaining reaction so long as the system is started once.

Am I crazy for this? I can see it working, but I haven't built a test model to see if it would actually work.

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thegagis t1_iulleq3 wrote

Boiling stops immediately if you stop making the boiling happen with heat. Water boils if and only if you dump a lot of energy into it somehow. It does not produce free energy from nothing.

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TheNoobsauce1337 t1_iulltb8 wrote

But that's the thing. Part of the electricity in the generators would be re-routed back to the boilers to maintain the heat. Would that be possible?

Basically the water is constantly boiling, the generators have two circuits. The larger circuit powers the engine, the smaller circuit maintains heat in the boilers.

Would that be possible?

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SLR_ZA t1_iulm949 wrote

No, you cannot power a generator with steam then take part of that energy to make as much steam as powered the generator.

You require more energy to make the steam than you can recover from the steam max.

Cut out the electric generator and just imagine boiling water with steam to make steam.

You're trying to do that and get more steam out than went in plus enough to overcome the turbine and battery efficiency and have usable power left over for the ship

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TheNoobsauce1337 t1_iulmgzn wrote

Ahh I see.

Believe it or not, I wasn't posting this to troll. I legit had a scientific question and wanted to test the idea out with other like minds.

Contrary to what you see on today's internet, I actually appreciate the criticism. Bouncing ideas back and forth (pending real experimentation) is what I think makes science both great and important. Seeking out truth through hypothesis and experimentation.

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TheDawggFather t1_iulqdch wrote

This curiosity you have is great! However, It seems you might be operating without fully understanding some fundamental physical concepts. If your really interested in these kinds of things, im sure you would enjoy taking some time to learn more physics and engineering. I know that YouTube has some awesome video lectures and I've heard good things about Brilliant.com. I hope this helps, never stop being curious and asking questions! 👍

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dudius7 t1_iulm9q2 wrote

No it would not be possible. You're talking about something like a perpetual motion machine.

If you used a battery to power an internal colandria to generate steam, then used that steam to power a turbine, you would have energy losses. Those losses would prevent you from recharging the battery, powering the colandria, and propelling the ship.

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