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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

#161

Post by onlyrealcuzzo »

anonporridge wrote: post #14
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.

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!

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

#162

Post by pharke »

If we converted all energy production to geothermal, would it be possible to significantly increase the cooling of the Earth's core?

The flow from the Earth's core to the surface is estimated at 47±2 terawatts[0]

The total energy supply for 2017 was 162,494 TWh[1]

World energy demand is expected to grow 27% by 2040

Currently, heat escaping from the Earth accounts for only 0.03% of Earth's total energy budget at the surface which is dominated by the 173,000 TW contributed by solar radiation[0] What effect would it have if the vented heat were equal to the amount contributed by the sun?

[0] https://en.wikipedia.org/wiki/Earth%27s_internal_heat_budget

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

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

#163

Post by ijidak »

peterburkimsher wrote: post #151
XorNot wrote: post #113

Earlier quoted context omitted.

Option C: it doesn't solve enough problems for oil and gas to have been worth pursuing compared to iterative improvements to existing systems. Whereas for geothermal, conventional drilling isn't useful enough for it.

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.

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

#164

Post by jmacd »

tinco wrote: post #159
leoedin wrote: post #56

Earlier quoted context omitted.

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.

A 60m borehole is not a source of energy, it is a store of energy. It only makes sense if you can sink enough heat into it in the summer, to use that energy in the winter. Or vice versa in warmer climates.

We have a ground source heat pump and one summer we were away and did not use out air conditioning that year much at all. Mid winter our return loop temperatures (the glycol being brought in to our heat pump after circulating in the ground) was at one point 3 degrees C cooler than it had been any other year. Quite a noticeable difference. For reference, our loops are 8 vertical at 250ft.

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

#165

Post by jmacd »

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.)

You have to make sure it's straight, drop sheathing in to the hole, and then cap it if it isn't going to be used right away.

More importantly, geothermal/ground source is rarely 1 well either, in our case it was 8.

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

#166

Post by raducu »

kragen wrote: post #97
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.

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?

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

#167

Post by oceanplexian »

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…

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 sufficiently resilient from the problem. There is no “if” here, it’s statistically guaranteed.

As far as I know, the best way for humanity to advance technology is with growth. More people with a higher standard of living means more teachers, scientists, artists, engineers, and leaders. We need those people because hiding in a cave is exactly the wrong thing to do.

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

#168

Post by FredPret »

jmacd wrote: post #164
tinco wrote: post #159

Earlier quoted context omitted.

A 60m borehole is not a source of energy, it is a store of energy. It only makes sense if you can sink enough heat into it in the summer, to use that energy in the winter. Or vice versa in warmer climates.

We have a ground source heat pump and one summer we were away and did not use out air conditioning that year much at all. Mid winter our return loop temperatures (the glycol being brought in to our heat pump after circulating in the ground) was at one point 3 degrees C cooler than it had been any other year. Quite a noticeable difference. For reference, our loops are 8 vertical at 250ft.

Wait, do you need eight 250ft wells?

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

#169

Post by FredPret »

oceanplexian wrote: post #167
Joeri wrote: 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…

From this point of view, which I certainly share, the responsible thing to do is to grow as fast as humanly possible until we are spread far and wide across the solar system, while also hedging our bets and making an effort to grow in the cleanest way that doesn’t slow us down.

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

#170

Post by throwaway9870 »

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 uniformly 1000 deg F, it wouldn't help us because we don't have a temp differential to convert thermal energy to electric.

Nowhere in the article did I see them mention temp differential and where they are going to dump the waste heat? Nuclear plants get crapped on because they dump heat into adjacent water bodies, how is this different?

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