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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

#61

Post by erosenbe0 »

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…

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.

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

#62

Post by Glawen »

eru wrote: post #16
Glawen wrote: post #10

Yeah right. They drilled in Strasbourg, France, to get this "free" energy. When they entered production, the city was experiencing an earthquake every month, waking the city at night. After a magnitude 4 earthquake, they finally shut down the plant. A town in Germany is devastated also due to geothermal power: https://en.m.wikipedia.org/wiki/Staufen_im_Breisgau

Assuming this is a real problem, wouldn't you just put your geothermal power plant well outside of any city? Doesn't even have to be somewhere where there are no buildings. Just somewhere where hardening the few existing buildings against small earthquakes etc won't be too expensive.

The goal of the plant was to provide heat for Strasbourg, so it has to be near the city.

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

#63

Post by modeless »

TeeMassive wrote: post #34

I've always wondered, but geothermal plants are basically huge radiators. If Humanity taps into this energy in industrial scale for centuries, would we cool the planet's mantle and core enough to have repercussions on the magnetic field for example?

20 km is 0.3% of the way to the center of the earth. It seems unlikely that anything we do there could affect the core in a meaningful way.

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

#64

Post by ComradePhil »

axiolite wrote: post #52
ComradePhil wrote: post #32

Earlier quoted context omitted.

We can pump heat into the core when it is hotter in the surface. So, it can also work as a battery.

> We can pump heat into the core when it is hotter in the surface. Were you expecting a massive meteor impact in the near future that the rest of us are unaware of? If not, exactly how were you planning to get enough heat at the surface of the Earth to warm-up the core?

Do you think we drill to the very core to get thermal energy? Well, I have disappointing news for you: The earths radius is 6,371 km; for thermal plants, we dig like 5 km.

While the core is 5000 degrees celcius, the point we dig to is more like 150. Concentrated solar power can generate 1000 degree celcius. If we pump this down when we have excess, the area remains hotter than it would otherwise be... letting us use it when the sun sets. This can also work through much longer timescales, like you could dump energy heat down in the summer and harvest it in the winter.

The post I was replying to was worried about gradual loss of core heat. This will be minimized if we pump heat in.

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

#65

Post by numpad0 »

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.

Agriculture relies on stable water supply…

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

#66

Post by erosenbe0 »

hattmall wrote: post #13
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…

That's a pretty solid question. I really don't know but hopefully someone else can answer. My guy hypothesis though is that even for all of our energy demands the amount pulled out would be pretty negligible. The reason being that only like 0.1% of the earth covered with solar panels would meet all our energy demands and heat wise geothermal should be much more efficient. The issue with heat and global warming isn't…

It's a non issue. But suppose you had a localized gigawatt leak into some wetlands. That would be trouble.

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

#67

Post by mkl »

ChuckMcM wrote: post #58
Glawen wrote: post #10

Yeah right. They drilled in Strasbourg, France, to get this "free" energy. When they entered production, the city was experiencing an earthquake every month, waking the city at night. After a magnitude 4 earthquake, they finally shut down the plant. A town in Germany is devastated also due to geothermal power: https://en.m.wikipedia.org/wiki/Staufen_im_Breisgau

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 to meet when they are 6+ miles deep.

I'm doubtful that any drilling process can be that straight and accurate unless straight lines are inherent in the drilling process (e.g. lasers somehow). Just think of how much trouble they had drilling to those stranded Chilean miners to rescue them, only 700m down: https://en.wikipedia.org/wiki/2010_Copiap%C3%B3_mining_accid...

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

#68

Post by dzhiurgis »

A few Lithuanian names there. They’ve apparently tried geothermal in Klaipeda but faced salt water which was hard to handle.

Generally Eastern European cities with centralised heating are very suited for geothermal. Except they’ll loose all that sweet sweet kickback from Russian oil dealer.

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

#69

Post by erosenbe0 »

ZeroGravitas wrote: post #54

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.

You cut out the combustion stack and boiler here so it has to be much cheaper than fossil fuel turbine?
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