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0 pointscerealbad7y ago0 comments

a seebeck generator can exploit airflow above or depth below oceans to convert heat into electricity. what uniform heat? all human heat effects augment the existing temperature cycles which have baked in gradients. thermoelectric processes simply reverse this, it would cause a lot of rain and raise ocean levels as the excess atmospheric water vapor is returned to a liquid state- due to the transformation of heat into electricity which would be stored or used to move the little sea robots around.

is the sun uniform heat? how do ectothermic animals and plants using photosynthesis work? I'm not sure why you think you can magically break thermodynamic symmetry...

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drdeca7y ago· 2 in thread

A seebeck generator “converts a heat flux into electrical energy” (Wikipedia), it does not convert heat into electricity.

(Edit: by which I mean, it does not decrease the total amount of heat in the system.)

You need something colder on the other side.

The sun-earth system is not uniform in heat, no. The sun on average is hotter than the earth on average.

Edit: what thermodynamic symmetry are you referring to?

cerealbadOP7y ago

the mechanism that generates heat is reversible, that's how we got fossil fuels to begin with (hydrocarbon storage). if you think converting heat flux into electrical or mechanical energy doesn't reduce the total heat flux of the system then it's a perpetual motion engine? you get more energy out than you put in? think it through.

it's powered by a heat differential, you are draining the heat from the system and storing it or dissipating it under motion - reducing the overall flux - over time by cooling the hot side and heating the cool side eventually some equilibrium is reached, depending on how efficient the throughput is and how much heat you have, you then exhaust your temperature gradient and need to move somewhere hotter or colder.

one of us is very confused here. i claim "you can reduce heat locally in the earth system", and give examples: capturing and insulating it (trees, plants), converting it into other types of energy (genetically modified sea sponge/robots), as well as venting it into space through an atmospheric/orbital seebeck ring.

im not breaking any laws of thermodynamics, i am turning the planet into a refrigerator.

edit: to clarify i am claiming it's possible to move heat away from the habitable thin boundary layer by conversion: storage, mechanical use or venting.

drdeca7y ago

I agree that converting heat flux (or, uh, temperature gradient? I think I might actually mean temperature gradient) into electrical or mechanical energy reduces the amount of heat flux ( or temperature gradient) of the system.

Reducing the temperature gradient(s) of the system does not reduce the amount of heat in the system. When the temperature gradient decreases, that just means that there isn’t as much variation in the temperatures in the system. The temperatures become more uniform. When the temperatures are uniform, you cannot use the temperature in order to do useful work.

.. I now notice that I missed that you mentioned putting things into orbit?

I misunderstood and thought you meant putting the seebeck stuff in the ocean, as if that would cool down the oceans.

Yeah, if you pump heat into places that you can remove from earth, or have emit black body radiation more effectively, that would help.

But, Unless you are ejecting stuff away from earth, there is still a max rate you can radiate away heat at a given temperature? Oh, but, hm, if you made your thing in orbit really really hot, hm.

Is that what you were saying?

Sorry for misunderstanding what you meant about the ocean.

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