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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

#71

Post by Someone »

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…

> They’re digging one mile (1.6 km) holes dropping low enriched nuclear fuel to the bottom, and filling them with water.

> When the fuel is used up, they can leave it where it is since it’s below the water table.

To do both, they’ll have to guarantee that that column of water stays isolated from groundwater for a long time after the fuel is used up.

Reading https://www.deepfission.com/faq, they answer that question with

“Importantly, the mile-deep column of water in the borehole is expected to provide the pressure conditions required for safe reactor operation. Water within the borehole is also intended to contribute to the reactor’s thermal management system”. So, what do they do if their drill hole starts leaking, and they lose pressure?

and

“Our boreholes are expected to be lined with multiple layers of casing, including steel casing and concrete intended to maintain structural integrity and isolate surrounding geological formations”

I don’t think those are good answers. They say what they want to do, but almost nothing about how they’ll do that, and try to avoid making hard statements on the what by using “is expected” and “is intended”.

Re: Millimeter wave technology drills 100 meters into granite

#72

Post by tonyedgecombe »

UltraSane wrote: post #51
cyberax wrote: post #39

Earlier quoted context omitted.

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 percenta…

The water column is isolated fron the fuel. The weight of the water column just allows for a cheaper enclosure. https://www.nrc.gov/docs/ML2419/ML24191A372.pdf

Presumably once you are finished with it you could just fill it with concrete.

Or partially fill it and drop another reactor on top.

The only projects that overrun more than nuclear is nuclear waste disposal. This kills two birds with one stone.

Re: Millimeter wave technology drills 100 meters into granite

#74

Post by synctext »

willis936 wrote: post #54
UltraSane wrote: post #52

Earlier quoted context omitted.

The nuclear fuel is contained inside a reactor vessel. The water pressure just allows it to be much cheaper. https://www.nrc.gov/docs/ML2419/ML24191A372.pdf

Page 7 looks like a single point of failure in an unmaintainable device that would result in a well of contaminated water a mile deep that passes through the water table that could never be fixed. This sounds like the worst idea I've ever heard.

Yeah, 76cm (30 inch) bore hole drilling with standard oil&grass rig.

Fill with unshielded nuclear reactor of novel type: super skinny.

Gently lower down until depth of 1 mile is reached.

Repeat 1000x for a 1 GWe power plant.

What could possibly go wrong? Best horror story of the year in 15 slides.

Re: Millimeter wave technology drills 100 meters into granite

#75

Post by cucumber3732842 »

Someone wrote: post #71
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…

> They’re digging one mile (1.6 km) holes dropping low enriched nuclear fuel to the bottom, and filling them with water. > When the fuel is used up, they can leave it where it is since it’s below the water table. To do both, they’ll have to guarantee that that column of water stays isolated from groundwater for a long time after the fuel is used up. Reading https://www.deepfission.com/faq , they answer that question…

>I don’t think those are good answers.

Steel and concrete are what we use above ground so.....

>They say what they want to do, but almost nothing about how they’ll do that, and try to avoid making hard statements on the what by using “is expected” and “is intended”.

They say nothing about how because those are trivial problems in the well (and oil) drilling industry.

Re: Millimeter wave technology drills 100 meters into granite

#76

Post by cucumber3732842 »

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

I greatly dislike this sort of "doesn't work perfectly everywhere by default therefore doesn't work" take. The steam engine didn't replace all the mules at once.

It should be pretty trivial to pick and choose geologies and depth where it is safe. Maybe that's a lot of places. Maybe that's a few. But it should be trivial regardless.

Re: Millimeter wave technology drills 100 meters into granite

#77

Post by willis936 »

willis936 wrote: post #54
UltraSane wrote: post #52

Earlier quoted context omitted.

The nuclear fuel is contained inside a reactor vessel. The water pressure just allows it to be much cheaper. https://www.nrc.gov/docs/ML2419/ML24191A372.pdf

Page 7 looks like a single point of failure in an unmaintainable device that would result in a well of contaminated water a mile deep that passes through the water table that could never be fixed. This sounds like the worst idea I've ever heard.

Also, I want to add on that if you lined the well to be single fault tolerant you will still be vulnerable to a high likelihood common mode failure from a single seismic event. Truly just the worst. The founders should pivot hard and fast.

Re: Millimeter wave technology drills 100 meters into granite

#78

Post by Asooka »

Someone wrote: post #71
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…

> They’re digging one mile (1.6 km) holes dropping low enriched nuclear fuel to the bottom, and filling them with water. > When the fuel is used up, they can leave it where it is since it’s below the water table. To do both, they’ll have to guarantee that that column of water stays isolated from groundwater for a long time after the fuel is used up. Reading https://www.deepfission.com/faq , they answer that question…

> To do both, they’ll have to guarantee that that column of water stays isolated from groundwater for a long time after the fuel is used up.

I wonder if just letting the water gradually dissolve the uranium might not be fine, actually. If it is done far from wells and rivers used for drinking water, then the small amount of radioactive minerals that slowly seep out might not pose a danger. I can't find any studies to back it up, but I imagine there are places on Earth at which enriched uranium buried 1.6km underground poses no threat. I am no expert, so I would love to hear what others think.

Re: Millimeter wave technology drills 100 meters into granite

#79

Post by UltraSane »

willis936 wrote: post #54
UltraSane wrote: post #52

Earlier quoted context omitted.

The nuclear fuel is contained inside a reactor vessel. The water pressure just allows it to be much cheaper. https://www.nrc.gov/docs/ML2419/ML24191A372.pdf

Page 7 looks like a single point of failure in an unmaintainable device that would result in a well of contaminated water a mile deep that passes through the water table that could never be fixed. This sounds like the worst idea I've ever heard.

A mile is much deeper than the water table is almost everywhere. It is normally solid bedrock. So you can just fill the hole with concrete and dirt.

Re: Millimeter wave technology drills 100 meters into granite

#80

Post by UltraSane »

willis936 wrote: post #77
willis936 wrote: post #54

Earlier quoted context omitted.

Page 7 looks like a single point of failure in an unmaintainable device that would result in a well of contaminated water a mile deep that passes through the water table that could never be fixed. This sounds like the worst idea I've ever heard.

Also, I want to add on that if you lined the well to be single fault tolerant you will still be vulnerable to a high likelihood common mode failure from a single seismic event. Truly just the worst. The founders should pivot hard and fast.

There are plenty of places with very little seismic activity.
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