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Tidal energy is not renewable

cs.stanford.edu

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Re: Tidal energy is not renewable

#2

Post by hirundo »

> ... if we were to extract the rotational energy just to supply 1% of the world's energy consumption, the rotation of the Earth would lock to the Moon in about 1000 years ... and most life on Earth could be wiped out.

Important safety tip.

Re: Tidal energy is not renewable

#3

Post by uoaei »

Then technically neither is wind, since it slows down surface air currents and widens the effective boundary layer of the atmosphere.

Technically-technically, no forms of energy "generation" (technically just conversion) are 100% efficient so something is always lost to heat. I guess the important question is, what is the net effect in changing that kind of energy into purely thermal energy?

Re: Tidal energy is not renewable

#5

Post by jval43 »

uoaei wrote: post #3

Then technically neither is wind, since it slows down surface air currents and widens the effective boundary layer of the atmosphere. Technically-technically, no forms of energy "generation" (technically just conversion) are 100% efficient so something is always lost to heat. I guess the important question is, what is the net effect in changing that kind of energy into purely thermal energy?

Isn't wind created by temperature and pressure differentials between regions? How much is due to earth's rotation?

Re: Tidal energy is not renewable

#6

Post by caesil »

hirundo wrote: post #2

> ... if we were to extract the rotational energy just to supply 1% of the world's energy consumption, the rotation of the Earth would lock to the Moon in about 1000 years ... and most life on Earth could be wiped out. Important safety tip.

There's an award-winning sci-fi book with a tidally locked planet as its premise: https://www.goodreads.com/en/book/show/37534907

Re: Tidal energy is not renewable

#8

Post by uoaei »

jval43 wrote: post #5
uoaei wrote: post #3

Then technically neither is wind, since it slows down surface air currents and widens the effective boundary layer of the atmosphere. Technically-technically, no forms of energy "generation" (technically just conversion) are 100% efficient so something is always lost to heat. I guess the important question is, what is the net effect in changing that kind of energy into purely thermal energy?

Isn't wind created by temperature and pressure differentials between regions? How much is due to earth's rotation?

Quite a lot because of thermal expansion/contraction of air and differentials in incident sunlight heating the surface at different points at different times. Albedo, thermal mass of the objects being heated, etc., all contribute to a complex system of air and energy transport via air currents.

It would take quite a lot of planning and work but maybe there are ways to mitigate these losses by balancing out the effects between different processes. Typically nature finds such dynamic equilibria as a matter of course -- I suspect anything humans attempt to control will not be as resilient or sound.

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