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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

#231

> Meanwhile, the heat vitrifies the side of the hole, turning it essentially into a glass pipe I think this is pretty essential and maybe even more important than the depth. Until now it was not economically feasible because the porous rock did swallow a lot of the circulated water in such a drilling. But this technique seems to solve that problem pretty effectively.

Conventional boreholes are cased with steel and cement. Vitrified walls would theoretically save that material cost (if it actually worked)

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

#232

The idea of drilling deep geothermal to repurpose existing fossil plants is an elegant one. I imagine others have thought of this before, but it was new to me. Being able to take over the existing equipment (turbines, power transmission connections) seems appealing. Of course, it all depends on how expensive the drilling process is vs. the existing capital asset in the turbines, but maybe you could hit a price point…

ENergy conversion equipment can't easily be re-purposed for geothermal. The temperatures are usually much lower, and the working fluids are often hydrocarbons instead of steam.

Quaise seems to think it's possible:

> “What we intend to do is go to existing power plants—it could be a coal power plant, it could be a gas power plant, any of the thousands of fossil-fired power plants that exists in the United States and around the world—and we will propose to them to create a small geothermal field around them, which is matched to the turbine specification of the power plant. What comes out of the ground is steam that feeds into the turbine, and the rest is what they’ve always done. The turbine creates electricity. The plant is already connected to the grid,”

https://www.powermag.com/a-game-changing-vision-for-geotherm...

Could just be marketing fluff; I'm not an expert here. But don't coal plants exclusively use steam turbines?

Edit: Seems that lots of energy in the US comes from steam turbines: https://www.eia.gov/energyexplained/electricity/how-electric....

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

#234
post #154

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…

> GHG reduction The fixation on GHG reduction is, as a friend of mine puts it, a suicide pact, simply reducing the second derivative. Unfortunately it's easy to understand and discuss, so that's where all the attention goes. The issue of climate repair (and long term curation, unfortunately) seems to frighten lots of people. There are people working on it, but they are a small community.

Keywords for learning more about ‘climate repair’?

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

#235
post #173

and suffer the fate of krypton? sorry, I couldn't read the article without solving the question of energy cycle in my mind. renewable sources like solar, wind are kind of taking energy from outside, so in case of geo-thermal, if we keep using that, there is nothing thats balancing the equation.

You are right, this tech would cause the core to lose temperature at a slightly higher rate than otherwise. At the moment the earths core is cooling at the rate of 0.1 °C per million years from the current temperature of about 5,100 °C, interspersed with periods where the temperature loss is stopped or reversed because of gravity forces [0]. But any conceivable number of deep geothermic wells would not affect that rate in any measurable way.

[0] https://en.wikipedia.org/wiki/Earth's_inner_core

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

#236

This sounds like cool tech, and the re-use of the existing generation assets is clever, but just running costs of the steam part of an existing plant struggles to compete on a financial basis with wind turbines and solar PV so it'll probably only ever be a niche thing. Shared ground loops connected to heat pumps are a more boring tech with more potential to have a global scale impact.

Assuming that people commit to buying 24/7 carbon-free energy at any price, on-demand generation like geothermal will be quite valuable during the times when wind and solar are underperforming.

So geothermal will mainly compete with nuclear and storage, not wind and solar.

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

#237
post #163

Earlier quoted context omitted.

> Geothermal heating provides unlimited fuel for people in houses, staying still This sounds like the beginning of a great sci-fi novel. A future where Earth's core has cooled because of excess draws to power humanity. Now, the planet is losing it's magnetic field. To save humanity, humans need to re-heat the core, build biospheres, or leave the planet.

sounds similar to the plot of The Core (it was not great)

It's surprising how often that movie comes up, especially given how it's often accompanied by a note that it's not good. I suspect it's hit a pseudo-cult classic film status. The last few times I've seen it mentioned I've had the desire to seek it out and watch it again since I only remember bits and pieces.

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

#238
post #154

Earlier quoted context omitted.

> GHG reduction The fixation on GHG reduction is, as a friend of mine puts it, a suicide pact, simply reducing the second derivative. Unfortunately it's easy to understand and discuss, so that's where all the attention goes. The issue of climate repair (and long term curation, unfortunately) seems to frighten lots of people. There are people working on it, but they are a small community.

Keywords for learning more about ‘climate repair’?

Literally “climate repair” and “climate restoration”. Some NGOs to check out include the Centre for Climate Repair at Cambridge and Foundation for Climate restoration.

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

#239
> The microwave beam is hot enough to evaporate rock, and the vaporized rock is pumped back to the surface.

Is this part harder than it sounds? Do you need to keep it as hot vapor until it gets to the surface? What do you do with it then? Presumably a 12 mile column of rock turns into a whole lot of vapor. Is it toxic? When vaporized rock cools, does it become just sand, or are there interesting/concerning chemicals left over?

As a lay person, I'm never sure when I read about new tech to address environmental issues whether we're creating a new problem. We've spent generations aggressively pumping carbon out of the ground and into the atmosphere. Would a move towards rock-vaporizing drilling just mean aggressively pumping a bunch of silicon, iron, etc out of the ground and into the atmosphere?

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

#240
post #80

Earlier quoted context omitted.

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…

There is no such thing as sustainable growth. Eventually, one day, sooner or later a very unsustainable chunk of high speed space rock will hit the planet and wipe us out, or some other completely natural and “green” disaster, like a supervolcanic eruption, as has happened repeatedly in history. The only thing that will matter is if we advance our technology to a point to divert the problem or make ourselves sufficie…

I think if you are talking at that time scale, the imperative for humanity in particular to be the one to make that advancement is just anthro vanity. The history of humanity is such a relatively brief thing on the cosmic scale you are talking about, and yet in our brief time we have screwed things up massively for ourselves. But not necessarily for future species and human-like life.

Its ok if we don't make it guys, there was species before us, and there will be some after us. The universe is vast. We are probably not even that special, but we can do our best and enjoy life and try to minimize the suffering that will certainly happen from our mistakes... to want to "win" anything beyond that will just cause more suffering.

Its ok to admit we messed up, we couldn't know at the time that a global capitalism predicated on an unlimited nature would not end up great, the timeline of scientific discovery was not in out favor there. On all accounts we are most likely too late, its not anyone in particulars fault, its ok.

Time is very vast, that can scare you or humble you.

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