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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

#91

Post by hutzlibu »

pm90 wrote: post #44
Stevvo wrote: post #25

Earlier quoted context omitted.

Many countries have almost no wilderness left; everything is either urban or agriculture or mountains with no convenient place for an earthquake.

Seismic disturbances are generally a concern for dense urban areas. It seems unlikely that agricultural areas would care that much.

"It seems unlikely that agricultural areas would care that much."

Why would you think that? Because the peasants are all too stupid to notice an earthquake that damage their houses?

Sure, fewer people would be affected, than in a dense city, but the problem solution of: out of sight, out of mind, is fascinating.

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

#92

Post by re6fae5Wied5tha »

a1371 wrote: post #37
tschwimmer wrote: post #35

Earlier quoted context omitted.

I have to assume GP means that we should extract the geothermal heat at the bottom of the well/borehole, not by bringing the oil back up to burn it.

No, I mean we should use the motion of the water, not its heat. Like in hydroelectricity where water spins a turbine instead we are using a steam generator like gas fired plants

There's no reason to drill for this, and 6 miles down at 1000C presets less than ideal operating conditions for a turbine.

Any peak over about 2000ft should be sufficient for an atmospheric water generation plant to produce enough water for a down hill hydroelectric plant to power the atmospheric water generation plant with single digit ambient RH, and much lower elevations can be used in high RH climes.

I would recommend orienting collectors to the windward side to exploit the local humidity gain, in lower RH climes.

One of my projects is actually a water condensation, hydroelectric and gas liquefaction combined cycle plant.

That said, bores in areas with deep ground water do present an interesting opportunity for pumped storage, with the caveat that the turbomachinery is back in the bore hole and that's a really inconvenient place to fix it when it breaks.

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

#93

Post by Rapzid »

imgabe wrote: post #15

How much energy is in the core of the Earth? What happens if we cooled the core to the point that it became solid? I’m guessing that would be bad, but is it something that’s not conceivably possible on any human timescale?

About 47TW of internal energy reaches the surface and it could take up to 90 billion years to cool so...

No, never with current technology.

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

#94

Post by popcube »

Joeri wrote: post #80
anonporridge wrote: post #23

Earlier quoted context omitted.

I've had the thought for a while now that it might be a good idea to start changing the climate change narrative to a problem of planetary heat engineering, not simply a problem of GHG reduction. The current narrative is largely defeatist and regressive. It's largely about rolling back growth and the amount of energy civilization has harnessed. But if the narrative was altered to be a heat engineering problem, then i…

Alright, I’ll try to pitch the counter argument. The current green movement narrative is the same it has always been: living within our means. The current fossil fuel driven economy is objectively unsustainable. Yes, you can geo-engineer your way out of the heat problem, but that doesn’t solve all the other problems resulting from unsustainable growth, and who knows what fresh problems this will create. What the gree…

yes, until now, scientists always can save us. but they just need one time...

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

#95

Post by tjoff »

ComradePhil wrote: post #27
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…

Solar is also trapping more energy than what would never be there. If the sun's rays just hit the ground, a portion of it would be reflected back. We're using dark material to aborb most of what would be reflected back and we end up trapping more energy than we should... Solar panels are around 15% efficient, which means 85% of this trapped energy is immediately converted to heat, heating the local environment... and…

So 0% reflection?

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

#96

Post by happytiger »

leoedin wrote: post #56
Animats wrote: post #45

Microwave drilling. It's a known thing at small scale.[1] If it can be done at larger scale, it ought to have other applications. Doing it downhole at the end of a long pipe string is going to be much harder than doing it in a factory. So why isn't this an industrial machining process already, like plasma cutting? GA Drilling was pushing plasma drilling back in 2018.[2] They're still pushing it, but not making holes.…

This could also have good use for ground source heat pumps - they're the most efficient, robust and consistent source of domestic heating we have, but require fairly deep (60m ish) boreholes. If digging could be quicker, easier or faster these heat pumps could be installed everywhere.

Except this technology is for after you get to the plate of rock at the bottom of topsoil unfortunately. They mentioned it in the article. You use conventional drilling to get to depth first.

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

#97

Post by kragen »

Animats wrote: post #45

Microwave drilling. It's a known thing at small scale.[1] If it can be done at larger scale, it ought to have other applications. Doing it downhole at the end of a long pipe string is going to be much harder than doing it in a factory. So why isn't this an industrial machining process already, like plasma cutting? GA Drilling was pushing plasma drilling back in 2018.[2] They're still pushing it, but not making holes.…

Conventional “mechanical” drilling isn’t very heat tolerant because heat softens metal. For oil and even gas drilling it doesn’t need to be; they’re located in cooler rock. For supercritical steam EGS heat tolerance is a sine qua non. Conventional approaches might still work best, but it’s also plausible that what’s best for gas isn’t best for EGS.

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

#98

Post by kragen »

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…

It could. The available fossil sensible heat energy is something like hundreds of millions of years of sunlight. Right now geothermal is uneconomic except in special situations, and human world marketed energy consumption is four orders of magnitude smaller than insolation, so it’s not yet a practical concern.

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

#99

Post by kragen »

erosenbe0 wrote: post #61
ComradePhil wrote: post #27

Earlier quoted context omitted.

Solar is also trapping more energy than what would never be there. If the sun's rays just hit the ground, a portion of it would be reflected back. We're using dark material to aborb most of what would be reflected back and we end up trapping more energy than we should... Solar panels are around 15% efficient, which means 85% of this trapped energy is immediately converted to heat, heating the local environment... and…

Already been there done that. Asphalt roads and roofs do this en masse and create some slight overnight heat storage in urban environments. Solar is just a marginal addition I believe.

Also, much more importantly, oceans.

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

#100

Post by kragen »

WalterBright wrote: post #70

If you drill a hole deep enough, you'll be unable to prevent the hole from collapsing in on itself. I wonder how deep that would be.

Conventionally you fill the hole with mud with the same density as the rock, avoiding this problem. You couldn’t drill into the inner core that way because it’s liquid, and maybe at some shallower depth you’d run out of candidate mud materials that will stay liquid at the relevant temperature, but given the right mud I think you could pass the Moho. So far, though, the problem is breaking drill strings.
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