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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

#81

Post by re6fae5Wied5tha »

cryptica wrote: post #55

I hope that investors did the math to ensure that the energy used to dig such a deep hole with microwaves doesn't end up consuming more energy than the hole will generate over its lifetime... Will the hole crack irreparably after a few months? Nowadays, there seems to be an epidemic of engineering neglect in terms of capital allocation. A lot of wealthy individuals who have the capital to invest in such projects do n…

I can't imagine it takes more than a few circuits of water through the bore to recover all of the energy, the static column of water alone would contain a non-trivial fraction of the energy required to drill the bore after equilibrating.

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

#82

Post by ChuckMcM »

mkl wrote: post #67
ChuckMcM wrote: post #58

Earlier quoted context omitted.

I believe you may have missed what these folks are doing differently. To put it into context, geothermal energy that taps underground water reservoirs near heat sources has been shown to cause earthquakes and other not good side effects. All of those effects are associated with water being released from aquifers that were previously sealed, or ground changes due to water incursion into previously dry structures (whic…

> Let's assume (and I don't know since I don't work for these guys but we need numbers if we're going to guess at things) that their "drilling" with microwaves technology leaves behind a 12" diameter hole that is > 6 miles deep. And we can drill two of those holes in such a way that they meet at their maximum depth. I'm imagining holes that start on the surface 100+ yards (or meters) apart drilled with a slight angle…

That is entirely fair. And per @animats comment it isn't clear they have managed to do anything "new" yet.

That said, microwaves (like lasers) do tend to go straight. So from the point they start using them going forward, I would expect it to be possible (not easy, but possible) to keep them in a straight path.

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

#83

Post by derefr »

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.…

> Anything that works would be used by the oil and gas industry, and if they're not trying it, one suspects it might not be working.

To flip that around: this would imply that the most under-investigated-in-industry approaches to deep hole boring would be the ones that destroy the economic value of any oil-and-gas in the ground, no? Ones that make the ground radioactive, perhaps. Or that would set any potential oil fields on fire, or react them away, or irrevocably mix a combustion-inhibiting azeotropic solvent into them.

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

#84

Post by hectormalot »

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.

I have one of those. The well is 170m deep. Took 2 guys about half a day to drill it, so that actually doesn’t seem excessive in terms of time required (mostly sand, no rock below my house).

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

#85

Post by OJFord »

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.

They can also be horizontal, covering a larger area at a much shallower depth.

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

#86

Post by re6fae5Wied5tha »

imranhou wrote: post #73

Is there a chance that the hole creates a mini volcano that cannot be stopped?

This is actually the risk I came here to mention about deep bores.

Bore first, build later, otherwise you may be the unlucky winner of a fluid formation trapped under a rigid formation in the local geology.

https://theconversation.com/a-mud-volcano-has-been-erupting-...

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

#87

Post by labster »

rland wrote: post #30
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…

I think there are other effects of increased CO2 concentration that are not well understood and could be catastrophic. Like ocean acidification. That actually scares me far more than the heat aspect.

> not well understood and could be catastrophic. Like ocean acidification

Look up carbonate compensation depth, your mind will be blown. Yes, researchers understand the effects of climate change because they have been looking at it for 40+ years. Being extra worried about climate change is a lot like climate denial, in that it doesn’t show trust in our scientists. There is no need to invent trouble — the challenges we know we will face are hard enough.

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

#88

Post by manarth »

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

A steam turbine essentially _does_ use the motion of the water.

In conventional hydroelectricity, gravity causes the motion through the energy differential of the waters' height.

In a steam turbine, the potential energy is from the high temperature of the water, and the energy input to rotate the turbine comes from the temperature differential of the steam cooling.

In theory you could capture the hydroelectric energy of the water on its way down a 12 mile hole, but that gravitic potential energy is negligable compared to the energy difference between superheated steam and water.

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

#89

Post by Rapzid »

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

Geothermal does use the "motion" of the water.

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

#90

Post by Archelaos »

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…

The heat is not the problem. It radiates into space quite quickly. The current world energy supply per year is over 160 TWh.[1] By comparison, the erruption of Mount Tambora in 1815 released aprox. 237.5 times more energy in a single incident (~38 PWh).[2] The problem at that time was not an extended (regional) heat wave, but the substances that entered the atmosphere and remained there for several years, causing a global weather change.

[1] https://en.wikipedia.org/wiki/World_energy_supply_and_consum...

[2] Other less spectacular examples: 160 TWh is equivalent of 5 to 6 times the energy released by the Mt. St. Helens erruption of 1980 (~28 TWh) or the 2004 Indian Ocean earthquake (~30.6 TWh), or half of the energy released by the 1883 eruption of Krakatoa (~232 TWh), or 1/4 of all nuclear bomb explosions so far (628 TWh). For this an other examples see: https://en.wikipedia.org/wiki/TNT_equivalent

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