The better reason for a cylinder instead of a cube is that a cylindrical structure has about 70% the wind resistance of a cubic structure of the same cross section, IIRC. It’s not simply that it looks cooler. But still it’s a dumb idea in either profile.
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How is one engineer pointing out the apparent flaws in another engineer’s design “getting in the way?” If they really do know what they’re doing then a naysaying YouTuber shouldn’t be able to stop them.
Shouldn’t those investors know if other engineers have identified potentially major issues with the project they are considering investing in? Shouldn’t government policy-makers know if there are more promising technologies they might want to subsidize instead? Shouldn’t everyone have a right to know if the current design has a potentially huge carbon impact for all that concrete?
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Or build on the idea, or at least be thoughtful in the criticism. The “what a bunch of dummies” tone is more than a little off-putting. It’s a hard problem and this is a plausible partial solution with plenty of challenges to solve. If it succeeds, that’d be great.
Source: I’m an engineer who has built a few “impossible” things. They were possible, turns out.
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Unless I’m standing around in my home which is adjacent to this tower, and when it falls, I will be personally… let’s say, inconvenienced. There’s something called stakeholders that really should have a say, not just inventors, investors and some kind of invisible, all-knowing force called the market. Oh, and btw, there will. be. government. subsidies.
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Especially considering that “the market” is exactly what gave us the fossil fuel industry.
Hell, “the market” used to be a place where you could buy and sell actual human beings.
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Another reason to go for the mineshaft idea. Other than flooding (not a big issue if well designed) it would be impervious to weather, and the worst-case failure scenarios would not cause any kinds of safety issue for the surrounding community. A hole in the ground is not a hazard for aircraft and is less of a visual blight on the neighborhood too.
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It might even be a way to throw a bone to the coal industry as we transition to renewables; buying up tapped-out mine shafts and hiring out-of-work mining engineers to oversee the tunnel-related aspects of the project.
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Assembling uranium nuclei is the way to go.
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Obligatory Kliban.
Also, imagine the federal funding that will arrive as soon as you announce that Russians are researching the same idea.
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I’m having a hard time following how the crane powers a turbine as it lowers the blocks.
I mean, I get that if I just drop the blocks and let the line out freely, that can power a turbine. But, don’t most cranes lower under powered control with the motor providing some resistance? Is it really just a brake holding it back from uncontrolled free fall? A break that’s generating waste heat in the process.
The train idea posted above looked interesting. That’s closer to a free fall with power generation providing the breaking. With enough trains, more like a flowing item and not tons of starts and stop like the crane going up to get the next block. The mine example sounded similar too.
Water works so well, since you can just adjust the size of the inlet valve to control the flow. No wasted trips to get the next gallon of water and send it down.
I think this is the largest in the county (at least until someone posts a bigger one). It’s even in WV too.
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There is. It’s the fourth law of Thermodynamics: the Law of Conservation of Credibility.
There are some edge cases (e.g. the Shanghai maglev train), but that merely helps illustrate that nobody really understands thermodynamics.
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(By turbine I assume you mean motor/generator) It works the same way that regenerative braking works on an electric car. Or really, same way that any electric generator works where you’ve got a mechanical force spinning a shaft. AC induction motors being turned by an outside force generate current (at least if the stator is getting an initial excitation current) that can go back through the drive and into the grid. Sometimes if you’re trying to slow down a large mass the energy that’s created is sent through large braking resistors if it’s not practical to send it to the grid. (Look up how diesel electric train brake resistors work.) But this system would be designed to send the energy into the grid as efficiently as possible.
Ideally you wouldn’t use a mechanical brake on this thing while it was in motion because, yes, that’s all wasted energy and defeats the purpose. But the system would need a mechanical holding brake for safety.
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It does work well, from an energy perspective.
My understanding is that the short-term economics aren’t great (longer payback time compared to other methods), but the plant lifetime is very long; there are pumped-hydro facilities built in the 60s that are still running strong. On the timeline of the full life of the plant they pay for themselves quite handsomely, but the short-term pain is high.
Plus, there’s the problem that you need a) surplus water, and b) steep elevation gains that are also not-too-challenging for construction. That narrows the field considerably before you begin.
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Oh, sorry, I get the mechanics part. Run a motor in reverse.
It’s the large block dangling from a wire in uncontrolled free fall with only the generator resistance slowing it down. Plus the wasted trip to raise empty for the next block.
That’s the parts that seem questionable. For all the same reasons a car doesn’t use only regenitive breaking.
The generator can be geared to provide significant resistance. Properly designed, there wouldn’t be anything close to free fall.
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Don’t these same engineers give us safe commercial aircraft, buildings that don’t fall down, precision manufacturing, etc.? (No, I’m not an engineer… but I do have respect for the profession.)
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If cars were designed to spend most of their time going downhill at a steady speed then you’d only need the brake pads for emergency stops.
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Or when the battery is full. 
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Hydro on a large scale requires quite a but of real estate.
It also requires stable soil.
You can’t put it on an existing river if that river’s a spawning ground (a problem in most of the Pacific NW).
It must be approved by the Federal Energy Regulatory Commission (can you say Johnson City flood?)
A tower is the least-cost solution, though a mine would be a dandy solution as well.
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Deep mineshafts require a lot of maintenance, mostly to keep from flooding from groundwater, and pumping that out consumes energy.
Some outfits do pump air into permeable yet sealed former gas reservoirs deep underground, and use that pressure to run generators during the night. I think salt domes work splendidly in those cases, but sandstones are also fine. Much of the country does have salt beds beneath, maybe former mines can be sealed and used. I don’t think the salt mines are deep enough to have much gravitational potential.
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