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by asimpletune 1525 days ago
Stupid question but is it possible to cool the earth’s core if this tech was scaled out and used massively?
3 comments

No. (1) because just how massive the Earth is a number you don't fully comprehend, and (2) because the Earth is actively warming itself from ongoing decay of nuclear isotopes which sunk to the center during it's molten phase, so really we're just tapping into a big pile of decay heat.
There's also a huge amount of internal friction created by the moon stretching and squeezing the earth, I believe that accounts for more heat than nuclear decay. Regardless, there's no way we can realistically impact planetary dynamics by blowing some cold water down tubes to the mantle, there's simply too much thermal mass - so yeah geothermal is a fantastic and reliable energy source.
>There's also a huge amount of internal friction created by the moon stretching and squeezing the earth

Wow, I hadn't even thought of that. How much heat does this produce, roughly? For context, the total heat lost from the earth's interior is about 47 TW according to another comment, so in order for the earth to not heat up I assume that moon friction heat + nuclear decay heat < 47 TW?

Not today, but maybe someday.

(1) - The geothermal heat flow from the Earth's interior is estimated to be 47 terawatts

(2) - Human production of energy is even lower at an estimated 160,000 TW-hr for all of year 2019. This corresponds to an average continuous heat flow of about 18 TW

[1]- https://en.wikipedia.org/wiki/Earth%27s_energy_budget#Earth'...

Wow 47 TW of heat for the entire earth is so much lower then I ever would have guessed.

The wiki says that its about .08W/m^2. That means it an area of 2-3 football fields only puts out as much heat as a single space heater.

No, because the heat comes out regardless. The difference is whether it is used on the way out.

Likewise for solar and wind.

There's the heat that comes out regardless, and the additional heat that comes out if you drill a bunch of boreholes down to let it out, accelerating the transfer.

That being said, it doesn't look like we'll get to a significant magnitude of effect for a long time.

The short answer is no, the long answer is no, but the really long answer is that everybody pretends that it's 100% safe but I guarantee nobody predicted global warming occurring when fossil fuels first started being used. There will be secondary effects, we just don't know what they are yet
Global warming was proposed in the early 19th century. A wee bit after fossil fuels started to be used, but still a long time ago.

The present trumps the future. The past kicks us in the arse

People predicted global warming occurring when fossil fuels started being used.

A very simple reality left in the footnotes of newspapers at the time, and then tabled to giant research papers and committees as this was the only consensus that was able to be reached by fossil fuel addicted committees. "lets plan to form a commission in a few years, to do a study in a few years and look at the results in a few years for re-evaluation".

"Secondary effects" is meaningless put up against well-known global catastrophe. Everything has secondary effects. New shoes means your old shoes go unused. Eating now makes you crap later.

What matters is the magnitude of the effect: how much difference does it make?

There will be no secondary effect of geothermal energy extraction even noticeable compared to the present unfolding global climate catastrophe. The latter is what deserves attention. Anything else is a petty distraction. Raising petty distractions from it is a fundamentally evil activity.

No one can predict anything when they don't have access to the larger model. Assuming the real world corresponds to big models rather than the small models and understanding people usually have.