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dangil t1_jchydwx wrote

99.99??% of this energy is reflected or reemited by earth

The problem is that this tiny fraction can eventually increase the total energy inside earth. Depends on how well earth can radiate energy.

But ideally we let it all go except for a tiny fraction that builds biomass. Basically every form of energy on earth available to humanity or not comes from the sun’s energy.

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the_fungible_man t1_jci0mls wrote

>Basically every form of energy on earth available to humanity or not comes from the sun’s energy.

Two significant exceptions come to mind:

  • Nuclear energy does not come from the Sun.

  • Geothermal energy is not powered by the Sun.

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viscence t1_jci1l90 wrote

Oddly enough you can somewhat argue about both of these, as billions of years ago the gravitational effect of what would become the sun had a significant impact in getting that energy into what would become the earth... or that nuclear energy comes from isotopes formed from previous stars. It just becomes a matter of definitions at some point though.

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dangil t1_jci19cf wrote

Heavy nucleus were forged in a Star. Not ours though

Geothermal energy is basically gravitational energy from the formation of the solar system. Also related to the sun.

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Grindipo t1_jcld3tw wrote

Is it you, Lord Kelvin ?

The heat inside Earth comes from the radioactive decay of, well, radioactive elements inside.

It is true that the accretion of a planet releases a lot af heat, but without the radioactivity, the Earth would have cooled in less than a billion year.

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