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Millimeter wave technology drills 100 meters into granite

thinkgeoenergy.com

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Re: Millimeter wave technology drills 100 meters into granite

#31

Post by MadnessASAP »

pfdietz wrote: post #27
MadnessASAP wrote: post #18

Earlier quoted context omitted.

You don't need a significant flow of argon, just enough to keep unwanted gasses out of the waveguide. It's possible there exists a material that is transparent to mm waves, airtight, and can survive the conditions at the bottom of the hole. In such a case they could cap the waveguide and prevent any gas leakage. I'm quite sure Quaise is well aware that Argon isn't cheap and are already exploring multiple avenues for…

SF6 is a horrifically powerful greenhouse gas, so I doubt it could be used. Its GWP is somewhere around 23,000 on a 100 year timescale.

Oh yeah, there's no shortage of reasons not to use SF6. Even in conventional waveguides, as far as I know most designs these days prefer nitrogen or dried atmospheric air.

Re: Millimeter wave technology drills 100 meters into granite

#32

Post by baron816 »

I really like what https://www.deepfission.com/ is trying to do. They have the absolute simplest model for nuclear fission that I can imagine. They’re digging one mile (1.6 km) holes dropping low enriched nuclear fuel to the bottom, and filling them with water. The pressure from the one mile column of water is perfect for the reactor. From there, it’s basically a geothermal well.

No need for an expensive containment dome, or expensive plumbing. If anything goes wrong, the nuclear fuel is already a mile underground. When the fuel is used up, they can leave it where it is since it’s below the water table. No need for expensive and hard to source highly enriched uranium.

The hard part is digging the wells, but that seems trivial compared to Quaise, who’s trying to dig 3-20km wells. The Deep Fission wells can just go anywhere (perhaps next to a disused former coal turbine?).

Re: Millimeter wave technology drills 100 meters into granite

#33

Post by rgmerk »

baron816 wrote: post #32

I really like what https://www.deepfission.com/ is trying to do. They have the absolute simplest model for nuclear fission that I can imagine. They’re digging one mile (1.6 km) holes dropping low enriched nuclear fuel to the bottom, and filling them with water. The pressure from the one mile column of water is perfect for the reactor. From there, it’s basically a geothermal well. No need for an expensive containment…

That sounds like an absolute nightmare to get approvals for.

Re: Millimeter wave technology drills 100 meters into granite

#34

Post by tliltocatl »

andai wrote: post #25

Can someone explain how this works? A gyrotron is some kind of maser (like a laser but with microwaves). Are they vaporizing the rock?

Gyrotron isn't quite a maser, more akin to a free-electron (i.e. electron beam) RF source. AFAIR (might be wrong, but based on what I could find there: https://www.thinkgeoenergy.com/wp-content/uploads/2021/03/mi...) they aren't literally vaporizing the rock, rather locally heating it til it crushes into particles that can be blown away.

Re: Millimeter wave technology drills 100 meters into granite

#35

Post by noja »

baron816 wrote: post #32

I really like what https://www.deepfission.com/ is trying to do. They have the absolute simplest model for nuclear fission that I can imagine. They’re digging one mile (1.6 km) holes dropping low enriched nuclear fuel to the bottom, and filling them with water. The pressure from the one mile column of water is perfect for the reactor. From there, it’s basically a geothermal well. No need for an expensive containment…

What are the side-effects of regularly detonating nuclear bombs at that depth?

Re: Millimeter wave technology drills 100 meters into granite

#36

Post by NonHyloMorph »

Might want to do yourself a favor and figure out the implied question behind 400(?) It's... not a lot of work. At least for me personally it rubs me the wrong way to name an important metric in Fahrenheit and then to give an estimate with a question mark for the proper SI unit.

Re: Millimeter wave technology drills 100 meters into granite

#37

Post by notrustincloud »

baron816 wrote: post #32

I really like what https://www.deepfission.com/ is trying to do. They have the absolute simplest model for nuclear fission that I can imagine. They’re digging one mile (1.6 km) holes dropping low enriched nuclear fuel to the bottom, and filling them with water. The pressure from the one mile column of water is perfect for the reactor. From there, it’s basically a geothermal well. No need for an expensive containment…

below and penetrating the water table with the potential for short and long half-life transuranic fissile products and a path of least resistance for any runaway conditions which is directly to an uncontained well head... with the extra bonus of installation proposed in 'spent' hydrocarbon bearing regions which implies reduced density substrates with all the tiny seismic outcomes and risks.

perfectly safe /s

Re: Millimeter wave technology drills 100 meters into granite

#38

Post by tliltocatl »

jauntywundrkind wrote: post #28
DoctorOetker wrote: post #21

Earlier quoted context omitted.

They mentioned about 1 hour per meter at 1 MW.

The video mentions that they did all the drilling so far at 100kW and are expecting to start doing 1 MW within the year. I wonder what their transmission voltage is. They're talking about a 1km deep shaft. That feels like a lot of conductor to get to 1MW, unless you can send at 20kV or something high. Reciprocally though if you're not transmitting major force through a drillshaft, perhaps it still is a major net win…

Based on what I could find:

They generate the RF on the surface and transmit it down the borehole thru a waveguide, so it's only limited by arching in the waveguide. Since we only need power transfer and don't care about multimode propagation, the waveguide diameter isn't limited, and probably on the larger side to reduce copper losses. And the heat management is provided by blowing argon which also carries abalated rock particulate to the surface.

See the schematics here: the schematic here: https://www.thinkgeoenergy.com/wp-content/uploads/2021/03/mi...

Re: Millimeter wave technology drills 100 meters into granite

#39

Post by cyberax »

baron816 wrote: post #32

I really like what https://www.deepfission.com/ is trying to do. They have the absolute simplest model for nuclear fission that I can imagine. They’re digging one mile (1.6 km) holes dropping low enriched nuclear fuel to the bottom, and filling them with water. The pressure from the one mile column of water is perfect for the reactor. From there, it’s basically a geothermal well. No need for an expensive containment…

It's an extremely stupid idea. Your whole water column is going to be contaminated with fission products. And you won't be able to get any reasonable amount of power out of that contraption.

And even if you are stupid enough to actually do this, the fuel efficiency will be terrible. Your only negative feedback for fission is the Doppler effect and thermal expansion. So you will only be able to utilize a tiny percentage of the fissionable materials.

Re: Millimeter wave technology drills 100 meters into granite

#40

Post by cyberax »

notrustincloud wrote: post #37
baron816 wrote: post #32

I really like what https://www.deepfission.com/ is trying to do. They have the absolute simplest model for nuclear fission that I can imagine. They’re digging one mile (1.6 km) holes dropping low enriched nuclear fuel to the bottom, and filling them with water. The pressure from the one mile column of water is perfect for the reactor. From there, it’s basically a geothermal well. No need for an expensive containment…

below and penetrating the water table with the potential for short and long half-life transuranic fissile products and a path of least resistance for any runaway conditions which is directly to an uncontained well head... with the extra bonus of installation proposed in 'spent' hydrocarbon bearing regions which implies reduced density substrates with all the tiny seismic outcomes and risks. perfectly safe /s

We can then build a primary school on top! And use the water from the well for heating directly.

What could possibly go wrong!?!?

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