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You can have geothermal power everywhere if you drill deep enough

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Re: You can have geothermal power everywhere if you drill deep enough

#11

Post by Uily »

anonporridge wrote: post #9

Something I've always wondered. Wouldn't massive scale geothermal end up pumping more heat into the atmosphere that otherwise wouldn't be there? In contrast, the energy collected by solar and wind generators is from the energy added to Earth by the sun and would be energy in our atmosphere regardless of whether or not we collect it. But it seems like the heat inside the Earth's core should be fairly well insulated by…

Yes, but it will be orders of magnitude less than the sum total energy of solar energy across the total surface of the earth.

Re: You can have geothermal power everywhere if you drill deep enough

#12

Post by eru »

Uily wrote: post #11
anonporridge wrote: post #9

Something I've always wondered. Wouldn't massive scale geothermal end up pumping more heat into the atmosphere that otherwise wouldn't be there? In contrast, the energy collected by solar and wind generators is from the energy added to Earth by the sun and would be energy in our atmosphere regardless of whether or not we collect it. But it seems like the heat inside the Earth's core should be fairly well insulated by…

Yes, but it will be orders of magnitude less than the sum total energy of solar energy across the total surface of the earth.

Similarly:

Nuclear power plants, as nearly all power plants, work by heating water. That heat has to go somewhere eventually.

But the amounts you'd need to make any difference to the atmosphere (compared to solar radiation) would be truly humongous.

Re: You can have geothermal power everywhere if you drill deep enough

#13

Post by hattmall »

anonporridge wrote: post #9

Something I've always wondered. Wouldn't massive scale geothermal end up pumping more heat into the atmosphere that otherwise wouldn't be there? In contrast, the energy collected by solar and wind generators is from the energy added to Earth by the sun and would be energy in our atmosphere regardless of whether or not we collect it. But it seems like the heat inside the Earth's core should be fairly well insulated by…

That's a pretty solid question. I really don't know but hopefully someone else can answer. My guy hypothesis though is that even for all of our energy demands the amount pulled out would be pretty negligible. The reason being that only like 0.1% of the earth covered with solar panels would meet all our energy demands and heat wise geothermal should be much more efficient. The issue with heat and global warming isn't the actual heat it's the thicker atmosphere not letting it dissipate fast enough.

Re: You can have geothermal power everywhere if you drill deep enough

#14

Post by anonporridge »

Uily wrote: post #11
anonporridge wrote: post #9

Something I've always wondered. Wouldn't massive scale geothermal end up pumping more heat into the atmosphere that otherwise wouldn't be there? In contrast, the energy collected by solar and wind generators is from the energy added to Earth by the sun and would be energy in our atmosphere regardless of whether or not we collect it. But it seems like the heat inside the Earth's core should be fairly well insulated by…

Yes, but it will be orders of magnitude less than the sum total energy of solar energy across the total surface of the earth.

Yeah. All civilization consumes around 17 TW of energy while the sun is constantly bombarding the Earth with 173,000 TW.

We could rebase all of civilization on geothermal and the extra heat in the atmosphere would be a rounding error to the sun's energy.

Re: You can have geothermal power everywhere if you drill deep enough

#16

Post by eru »

Glawen wrote: post #10

Yeah right. They drilled in Strasbourg, France, to get this "free" energy. When they entered production, the city was experiencing an earthquake every month, waking the city at night. After a magnitude 4 earthquake, they finally shut down the plant. A town in Germany is devastated also due to geothermal power: https://en.m.wikipedia.org/wiki/Staufen_im_Breisgau

Assuming this is a real problem, wouldn't you just put your geothermal power plant well outside of any city?

Doesn't even have to be somewhere where there are no buildings. Just somewhere where hardening the few existing buildings against small earthquakes etc won't be too expensive.

Re: You can have geothermal power everywhere if you drill deep enough

#17

Post by anonporridge »

eru wrote: post #12
Uily wrote: post #11

Earlier quoted context omitted.

Yes, but it will be orders of magnitude less than the sum total energy of solar energy across the total surface of the earth.

Similarly: Nuclear power plants, as nearly all power plants, work by heating water. That heat has to go somewhere eventually. But the amounts you'd need to make any difference to the atmosphere (compared to solar radiation) would be truly humongous.

I don't know if this would be any extra heat, because the radioactive material would already be decaying anyway if it was left in its natural state. Maybe the same problem where radioactive material would be left mostly underground and insulated where its heat would leak slowly.

Then again, part of the Earth's core heat comes form radioactive decay. So in a way, geothermal is an indirect form of nuclear fission.

Re: You can have geothermal power everywhere if you drill deep enough

#18

Post by eru »

Schroedingersat wrote: post #7

Assuming this works, tech still won't save us alone. Pure thermal (ie. just energy, no GHG) climate change is right around the corner if energy use keeps going up exponentially and we keep reducing earth's albedo. Ecosystems are still being obliterated for cattle and mining. All ghg free electricity will do is buy a few decades to end (and in the west, reverse) growth. Possibly the only thing that will give civilisat…

> Pure thermal (ie. just energy, no GHG) climate change is right around the corner if energy use keeps going up exponentially and we keep reducing earth's albedo.

What makes you think so? What growth rates are you assuming? How long is your time horizon?

Re: You can have geothermal power everywhere if you drill deep enough

#19

Post by eru »

anonporridge wrote: post #17
eru wrote: post #12

Earlier quoted context omitted.

Similarly: Nuclear power plants, as nearly all power plants, work by heating water. That heat has to go somewhere eventually. But the amounts you'd need to make any difference to the atmosphere (compared to solar radiation) would be truly humongous.

I don't know if this would be any extra heat, because the radioactive material would already be decaying anyway if it was left in its natural state. Maybe the same problem where radioactive material would be left mostly underground and insulated where its heat would leak slowly. Then again, part of the Earth's core heat comes form radioactive decay. So in a way, geothermal is an indirect form of nuclear fission.

Nuclear power plants don't just capture the energy from natural decay.

Though the precise mechanism doesn't matter too much for my comment. Just assume I'm talking about fusion plants.

Re: You can have geothermal power everywhere if you drill deep enough

#20

Post by tinco »

anonporridge wrote: post #9

Something I've always wondered. Wouldn't massive scale geothermal end up pumping more heat into the atmosphere that otherwise wouldn't be there? In contrast, the energy collected by solar and wind generators is from the energy added to Earth by the sun and would be energy in our atmosphere regardless of whether or not we collect it. But it seems like the heat inside the Earth's core should be fairly well insulated by…

You are correct in that the earth core is really well insulated from the surface. So well that the light of the sun delivers an order of magnitude more energy per M2 to the Earth's surface.

That information also answers your question, our problem isn't with the amount heat we produce, it's with how much of that solar radiation we trap in our atmosphere due to the green house effect of CO2 and similar gases.

So yeah we introduce a little bit more heat by drawing from the Earth's core, but it's nothing compared to what trapping the sun's energy with CO2 is doing to the planet right now.

Conversely using that energy to remove CO2 from the atmosphere might even cool the planet, but that's a question for the next generation.

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