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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

#191

Post by blibble »

hedora wrote: post #177
derefr wrote: post #83

Earlier quoted context omitted.

> 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 f…

I've long wanted to put some money into an eco terror fund. It would buy controlling interests in all the companies that make some critical, specialized and heavily patented piece of modern internal combustion engines or coal turbines. Then, it'd wreck the factories, and patent troll everyone else into not producing. Money is speech, and that would be protected political speech, right? :-)

that will result in those devices will be manufactured by the Chinese instead, and them then having a near monopoly

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

#192

Post by kragen »

raducu wrote: post #166
kragen wrote: post #97

Earlier quoted context omitted.

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.

But if we get to temperatures that destory metals, isn't it enough? Why don't we drill to whatever is the termal limit, make a big cavity there, install radiators there and just heat the watter to that temperature and take it out to surface where we can heat homes. I know this is done in Bucharest for a water park (to much lesser depths because apparently we have hot springs near Bucharest). Do we need to reach magma…

This is about running your air conditioner, charging your Tesla, and molding your kitchen sink, not heating homes. Think Carnot efficiency, power density, supercritical steam, and shutting down gas pipelines.

And the temperature to destroy steel under the immense mechanical stress of a drill string is surprisingly modest. Jet fuel can’t melt steel beams, but softening them is enough.

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

#193

Post by throwaway9870 »

marcosdumay wrote: post #174
throwaway9870 wrote: post #170

You just don't "use" heat to make electricity. You need some sort of heat engine running a cycle. All those require temperature differential. This is basic thermodynamics and isn't going to change with new technology. This temp differential is what is required to extract useful energy. So I don't understand why they talk about material at a certain temp having energy compared to oil. If we lived on a planet that is u…

Ok, with the sheer amount of red flags on the article, you chose that hill to die on? If you can get it anywhere, you go get it near the sea, and dump your heat there.

Heat exchangers running in ocean water are very difficult because they build up algae and other debris that can significantly reduce their efficiency.

None of this is rocket science, it is all well known to anyone who actually wants to do some research. Unfortunately, it seems like the people most vocal about energy are generally the least informed.

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

#194

Post by blibble »

ijidak wrote: post #163
peterburkimsher wrote: post #151

Earlier quoted context omitted.

Oil companies sell finite fuel for energy to people in cars, on the move. Geothermal heating provides unlimited fuel for people in houses, staying still. The technology is similar, and it's boring ;-) The market is different. This is an opportunity for entrepreneurs to hire expert drilling engineers out of the oil industry!

> 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)

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

#195

Post by hedora »

throwaway9870 wrote: post #193
marcosdumay wrote: post #174

Earlier quoted context omitted.

Ok, with the sheer amount of red flags on the article, you chose that hill to die on? If you can get it anywhere, you go get it near the sea, and dump your heat there.

Heat exchangers running in ocean water are very difficult because they build up algae and other debris that can significantly reduce their efficiency. None of this is rocket science, it is all well known to anyone who actually wants to do some research. Unfortunately, it seems like the people most vocal about energy are generally the least informed.

Putting the heat exchanger on a tethered weather balloon and floating it into low earth order addresses all those concerns.

It also doesn't involve rocket science.

QED.

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

#196

Post by [deleted] »

onlyrealcuzzo wrote: post #161
anonporridge wrote: post #14

Earlier quoted context omitted.

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.

So if our energy consumption increases by 4% per year (current global average) for ~110 years, we'd need to capture / produce as much energy as the Sun hits us with. Crazy!

[deleted]

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

#197

Post by NavinF »

dpark wrote: post #158
NavinF wrote: post #124

Earlier quoted context omitted.

I assume you mean “2 guys and some heavy equipment”? As a kid it took me a whole summer of on-and-off digging to make a 1 meter deep hole for fun.

Out of curiosity, what were you digging with? Unless you were digging with a toy sand shovel or making a very large hole, that seems like a very long time. As a kid, my cousin, my sister, and myself were able to dig a hole deep enough for me to be completely inside in an hour or two using a post hole digger. (Yes, this is a very stupid idea.)

A shovel. I couldn't get past 1m because of the rocks were too difficult to shatter.

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

#198

Post by throwaway9870 »

hedora wrote: post #195
throwaway9870 wrote: post #193

Earlier quoted context omitted.

Heat exchangers running in ocean water are very difficult because they build up algae and other debris that can significantly reduce their efficiency. None of this is rocket science, it is all well known to anyone who actually wants to do some research. Unfortunately, it seems like the people most vocal about energy are generally the least informed.

Putting the heat exchanger on a tethered weather balloon and floating it into low earth order addresses all those concerns. It also doesn't involve rocket science. QED.

I think you just proved my point better than I could have ever done: Those most vocal about energy are generally the least informed.

Let me guess, you have no formal engineering training, do you?

EDIT: to make this comment more constructive, here is a link to an excellent book on energy processes: https://www.amazon.com/Fundamentals-Renewable-Energy-Process...

I took a class with da Rosa and at the time this book was still in draft form, but nonetheless, excellent and easy to read. There appear to be new editions, don't know the differences.

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

#199

Post by eru »

masklinn wrote: post #185
eru wrote: post #141

Earlier quoted context omitted.

Huh? Read my comment. I did not suggest there are no building in non-urban areas. Just fewer, and thus it would be less expensive to make them earthquake proof. Japan deals with natural earthquakes all the time. Earthquakes stronger than whatever a bit of geothermal energy production would produce.

Because Japan deals with natural earthquakes all the time, japan has quake-safety standards. They were written in blood, and don’t exist in places which don’t routinely have earthquakes, because quake safety is constraining and expensive. Retrofitting an entire country for quake safety because you’ve decided to create artificial earthquakes is inane.

Who suggested an entire country? We are talking about small-ish areas.

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

#200

Post by hedora »

sidewndr46 wrote: post #175
hedora wrote: post #172

Earlier quoted context omitted.

Open challenge: Getting an elected US politician to seriously propose a space heat sink as a solution to climate change. There were some people seriously proposing big convection tubes that'd bootstrap columns of hot air, then passively pull surface air into the upper atmosphere. I can't find a link, but those wouldn't get to low earth orbit, so not a "space" technology.

I've heard of launching some large mirrors into orbit, or a bunch of small mirrors that can link together in orbit. Then you use them to reflect some sunlight off into space. I have no idea how practical this is. The bigger concern would be if something goes wrong, you need to make the mirrors deorbit quickly.

You could set it so that some of the mirrors formed a parabolic collector and heated a molten salt column, etc on the surface.

That'd have the same net effect as the giant heat sink (energy production from a heat engine, net negative flow of energy to the surface).

Wasn't there a city builder that'd let you build such a thing, where it would sometimes lose calibration and burn a swath of the city to the ground?

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