The Junk Drawer

DIY-HP-LED

Well-Known Member
I am sure that his stake in selling residential battery storage has nothing at all to do with it.

Geothermal using gyrotron drilling could blow a lot of renewables and even fusion out of the water, looks promising and has serious people behind it. I'm keeping an eye on this one.

This guy gives a pretty good over view that I posted before.

 

Roger A. Shrubber

Well-Known Member
I am sure that his stake in selling residential battery storage has nothing at all to do with it.

i don't like musk, but i think he might be right about this. by no means should they quit doing research, but do not slow down on wind and solar power production, on the off chance that there will be a break through tomorrow
 

cannabineer

Ursus marijanus
Geothermal using gyrotron drilling could blow a lot of renewables and even fusion out of the water, looks promising and has serious people behind it. I'm keeping an eye on this one.

This guy gives a pretty good over view that I posted before.

The vid has some serious logic issues. The quoted half-million cost to drill a 10-km borehole is energy only. What about the drill rig and the sleeving needed to stabilize the hole? What about the cost of separating out and disposing of the rock swarf?
How about not relying on an interested party’s (the company with zero boreholes demonstrated to date) figures? What of the fact that rock hot enough to be useful slumps under several dozen MPa of pressure?

One big miss is failure to discuss output energetics of, say, a 12-km borehole drilled at or near an existing coal-fired plant. Since bedrock is a poor heat conductor, the total energy a borehole can yield before the surrounding rock has been chilled to exhaustion is finite. What is that figure for the typical basaltic rock of deep crust? What power levels of extraction are realistic? How long does one borehole yield a usable level of power? What unintended consequences will generating volumes of rock chilled below the brittleness transition have?

So far, this impressed me as negatively as flying cars. Until someone shows me a flying car that is as good as a Cessna in terms of aerial range and economy — and will match a Toyota Camry’s lap time around the Nürburgring in street mode …

don’t wake me.
 
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cannabineer

Ursus marijanus
i don't like musk, but i think he might be right about this. by no means should they quit doing research, but do not slow down on wind and solar power production, on the off chance that there will be a break through tomorrow
We need something that is not sensitive to weather, and can be used in space past Saturn’s orbit.
 

schuylaar

Well-Known Member
The vid has some serious logic issues. The quoted half-million cost to drill a 10-km borehole is energy only. What about the drill rig and the sleeving needed to stabilize the hole? What about the cost of separating out and disposing of the rock swarf?
How about not relying on an interested party’s (the company with zero boreholes demonstrated to date) figures? What of the fact that rock hot enough to be useful slumps under several dozen MPa of pressure?

One big miss is failure to discuss output energetics of, say, a 12-km borehole drilled at or near an existing coal-fired plant? Since bedrock is a poor heat conductor, the total energy a borehole can yield before the surrounding rock has been chilled to exhaustion is finite. What is that figure for the typical basaltic rock of deep crust? What power levels of extraction are realistic? How long does one borehole yield a usable level of power? What unintended consequences will generating volumes of rock chilled below the brittleness transition have?

So far, this impressed me as negatively as flying cars. Until someone shows me a flying car that is as good as a Cessna in terms of aerial range and economy — and will match a Toyota Camry’s lap time around the Nürburgring in street mode …

don’t wake me.
Magnets.
 

DIY-HP-LED

Well-Known Member
The vid has some serious logic issues. The quoted half-million cost to drill a 10-km borehole is energy only. What about the drill rig and the sleeving needed to stabilize the hole? What about the cost of separating out and disposing of the rock swarf?
How about not relying on an interested party’s (the company with zero boreholes demonstrated to date) figures? What of the fact that rock hot enough to be useful slumps under several dozen MPa of pressure?

One big miss is failure to discuss output energetics of, say, a 12-km borehole drilled at or near an existing coal-fired plant? Since bedrock is a poor heat conductor, the total energy a borehole can yield before the surrounding rock has been chilled to exhaustion is finite. What is that figure for the typical basaltic rock of deep crust? What power levels of extraction are realistic? How long does one borehole yield a usable level of power? What unintended consequences will generating volumes of rock chilled below the brittleness transition have?

So far, this impressed me as negatively as flying cars. Until someone shows me a flying car that is as good as a Cessna in terms of aerial range and economy — and will match a Toyota Camry’s lap time around the Nürburgring in street mode …

don’t wake me.
Well MIT people are behind it and the physics works out on paper, they are drilling a test site over the next couple of years and attracting capital. Those vested in wind and solar might want to keep an eye on events and the results of tests. It might not be suitable for all locations, but could greatly impact renewable industries. I haven't seen too much professional criticism from the other articles I've read, everybody is wait and see when it gets into the real world. As for waste, that would be condensed basalt dust from a 10 Km bore hole, conventional drilling would get them to hard rock. If the oil companies go for it, you know it's for real, they are now in the energy business and this would be a good fit for them.
 

cannabineer

Ursus marijanus
Well MIT people are behind it and the physics works out on paper, they are drilling a test site over the next couple of years and attracting capital. Those vested in wind and solar might want to keep an eye on events and the results of tests. It might not be suitable for all locations, but could greatly impact renewable industries. I haven't seen too much professional criticism from the other articles I've read, everybody is wait and see when it gets into the real world. As for waste, that would be condensed basalt dust from a 10 Km bore hole, conventional drilling would get them to hard rock. If the oil companies go for it, you know it's for real, they are now in the energy business and this would be a good fit for them.
That sidesteps the energetics. It sounds like a sales job. And it will until proof of concept.

“the physics works out on paper” please elaborate. Not the drilling phase, the extraction of gigawatts over decades from an impermeable insulator phase.
 
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DIY-HP-LED

Well-Known Member
That sidesteps the energetics. It sounds like a sales job. And it will until proof of concept.

“the physics works out on paper” please elaborate. Not the drilling phase, the extraction of gigawatts over decades from an impermeable insulator phase.
Well details are few because it hasn't been done and I'm not an expert on the thermal conductivity of plastic or near liquified rock under that kind of pressure, physics gets weird at high pressures. I will watch the experts fight it out from the sidelines and so far they haven't said much. I assume such deep wells using super critical water would last for a very long time, dissolved minerals might be an issue eventually.

The major issue I see with it is collapse of the borehole at depth due to pressure and how thick would that glass fused drill casing be. We will see, that's what experiments are for and they will be conducting one.
 

cannabineer

Ursus marijanus
Well details are few because it hasn't been done and I'm not an expert on the thermal conductivity of plastic or near liquified rock under that kind of pressure, physics gets weird at high pressures. I will watch the experts fight it out from the sidelines and so far they haven't said much. I assume such deep wells using super critical water would last for a very long time, dissolved minerals might be an issue eventually.

The major issue I see with it is collapse of the borehole at depth due to pressure and how thick would that glass fused drill casing be. We will see, that's what experiments are for and they will be conducting one.
Supercritical water requires temps of 350+, not the ~200 quoted. Deep rock is frankly plastic at those temps and pressures.

So no.
 

DIY-HP-LED

Well-Known Member
Supercritical water requires temps of 350+, not the ~200 quoted. Deep rock is frankly plastic at those temps and pressures.

So no.
No to the experiment by experts in their field? I imagine geologists, as well as physicists are part of the team and MIT trains good physicists.
 

cannabineer

Ursus marijanus
I have no doubt there will be technical hurdles and the technology might even have to evolve through a couple of generations or more. We should have a better idea in a couple of years.
Longer, I think. Imo this is “Popular Mechanics”- style techporn not much different than 50 years ago, when it was proposed to orbit giant photovoltaic power stations that sent it down as large, hot microwave beams. That never came to be.

it follows that I don’t read Popular Mechanics. Their predictive success has been low.
 
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