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What it will take to unleash the potential of geothermal power? (2021)

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Re: What it will take to unleash the potential of geothermal power? (2021)

#41

Post by hunter2_ »

stevenpetryk wrote: post #34
nostromo wrote: post #31

I used to worry that might cool down the earth’s interior too quickly and regret it with mass geothermal. But waste heat ( not global warming from carbon, which is a separate and more pressing problem) will boil the oceans in a few hundred years on our current trajectory, and now I’m for cooling as much as possible however we can.

Apparently it could actually be beneficial to cool Yellowstone and prevent it from becoming active again.

I tried to search before asking, but only found the contrary. [0]

How does this work?

[0] https://www.usgs.gov/observatories/yvo/news/why-cant-we-dril...

Re: What it will take to unleash the potential of geothermal power? (2021)

#42

Post by applied_heat »

iancmceachern wrote: post #20

Make drilling cheaper. This would also help with water access. The biggest cost of small geothermal and water projects is always the drilling. Drill rig time is always a limiting factor.

I was hopeful that all of the unused drilling capacity after the shale boom/bust would allow some of the know how and equipment to be reallocated to geothermal but the grid operators and markets are not offering the premium to firm capacity that is required for the longer lead time and increased capital requirements and increased risk in geothermal projects vs wind and solar which can be augmented with battery storage.

It’s going to suck though when we hit a weeklong stretch of cloudy still weather if there isn’t enough spare capacity from other sources to compensate for the missing wind and solar.

Re: What it will take to unleash the potential of geothermal power? (2021)

#43

Post by nucleative »

adrianN wrote: post #2

>If prices come down, and if it can be deployed widely enough Drilling deep holes is expensive, prices are unlikely to come down much. Steam generators are expensive too.

Why is the cost of drilling so high?

I'm sure the rigs are an expensive capital outlay, but do the operators require advanced skills?

Once a hole is drilled, does it have a limited lifespan, or is that investment something that can be hypothetically used for eternity?

Re: What it will take to unleash the potential of geothermal power? (2021)

#44

Post by angiosperm »

gustavus wrote: post #6
porkbeer wrote: post #3

Does the widespread cooling of the planets interior have any possible consequences?

At the scales were talking about it's somewhere between Going to the beach and getting shot by a swimming dog carrying a gun in its mouth and the problems caused by doing flybys of Jupiter. https://what-if.xkcd.com/146/

Ironically, stealing momentum from Jupiter would speed it up.

Re: What it will take to unleash the potential of geothermal power? (2021)

#45

Post by greesil »

rmm wrote: post #15

I worked on a mining project years ago where we had to dewater the mine of 90 degree Celsius water at 700L/s. Always wondered whether we can use it for energy….

Ideal thermodynamic efficiency is 1-Tcold/Thot in an absolute temperature scale. This means given a perfect mechanism to turn heat into work this is the upper bound of how much of the heat can be turned into useful work.

Say ambient air is 20 deg C, with your 90 deg C heat source then you get 1-293/363 which is about 20%. So it's not to say you can't get work out of this system, but it's not great compared to having something nice and not.

And even then, you can't push a turbine with a hot liquid so your energy extraction technique now gets complicated.

Re: What it will take to unleash the potential of geothermal power? (2021)

#46

Post by fsckboy »

echelon wrote: post #27
iancmceachern wrote: post #20

Make drilling cheaper. This would also help with water access. The biggest cost of small geothermal and water projects is always the drilling. Drill rig time is always a limiting factor.

> Make drilling cheaper. How?

we can power it with free geothermal! the deeper the hole gets, the faster the drilling goes. it's power all the way down!

Re: What it will take to unleash the potential of geothermal power? (2021)

#47

Post by defrost »

iancmceachern wrote: post #40
echelon wrote: post #27

Earlier quoted context omitted.

> Make drilling cheaper. How?

I've been wanting to build and try something like this: https://youtu.be/3pOSzBgB8WU?si=kCyDZA0GkKMFAzNH Could easily be improved upon, seems workable

For shallow dirt holes, sure.

Not so great once the pressure increases or granite|schist layer intercede.

Re: What it will take to unleash the potential of geothermal power? (2021)

#48

Post by hunter2_ »

applied_heat wrote: post #42
iancmceachern wrote: post #20

Make drilling cheaper. This would also help with water access. The biggest cost of small geothermal and water projects is always the drilling. Drill rig time is always a limiting factor.

I was hopeful that all of the unused drilling capacity after the shale boom/bust would allow some of the know how and equipment to be reallocated to geothermal but the grid operators and markets are not offering the premium to firm capacity that is required for the longer lead time and increased capital requirements and increased risk in geothermal projects vs wind and solar which can be augmented with battery storag…

> if there isn’t enough spare capacity from other sources to compensate for the missing wind and solar

This seems like a problem Elon would gladly dabble in, pushing out a NACS firmware update or something as an emergency limiter. Maybe first responders get priority, like they do for mobile network congestion.

Or dirtier power remains on cold standby for unusual peaks. This would eventually be outlawed, I imagine.

Re: What it will take to unleash the potential of geothermal power? (2021)

#50

Post by iancmceachern »

defrost wrote: post #47
iancmceachern wrote: post #40

Earlier quoted context omitted.

I've been wanting to build and try something like this: https://youtu.be/3pOSzBgB8WU?si=kCyDZA0GkKMFAzNH Could easily be improved upon, seems workable

For shallow dirt holes, sure. Not so great once the pressure increases or granite|schist layer intercede.

I've been thinking one could add a water powered bit on the tip not unlike the tips they have on more traditional drill rigs. I think there is lots of room for improvement on this technique, lots of white space between this and a traditional rig.
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