https://www.techspot.com/news/97306-gravity-batteries-abandoned-mines-could-power-whole-planet.html
Tl;dr: lifting and lowering big weights in abandoned mineshafts has huge energy storage potential. Some of these shafts are incredibly deep!
Yeeeep. The school I last went to has been looking into this as well (it was originally founded as the Michigan Mining School during the Keweenaw copper boom, and naturally there are hundreds of abandoned shafts all over up there). The longest continuous shaft up there is over 9,000 feet.
They did an exploratory study on a mine complex in my town, too. This mine's main office/dry/etc. building was converted to the high school after the mine closed and the old HS across town was razed.
https://www.mtu.edu/unscripted/2022/05/modeling-the-mather-b-helps-map-out-future-for-old-mines-and-clean-energy-storage.html
It definitely makes sense to take advantage of existing infrastructure. I wonder how many usable mine shafts are close enough to the barren deserts out west, where solar farms can thrive?
Why not use them in active mines too? You leverage the poor dietary habits of the fattest miners by putting them on shifts timed to coincide with maximum grid usage.
Quote from: Morris Minor on January 19, 2023, 03:27:17 PM
Why not use them in active mines too? You leverage the poor dietary habits of the fattest miners by putting them on shifts timed to coincide with maximum grid usage.
Not possible. Below a certain level (depending on where you are, I guess) the shafts are constantly flooding. Massive, massive steam-powered pumps were used back in the day to keep the water out of the shafts. Same goes for modern open-pit mines...turn those pumps off and that pit very quickly becomes a small lake. Can't do this in an active mine.
Edit:
https://youtu.be/sDLpb6r80kA
Quote from: CaminoRacer on January 19, 2023, 03:25:12 PM
It definitely makes sense to take advantage of existing infrastructure. I wonder how many usable mine shafts are close enough to the barren deserts out west, where solar farms can thrive?
Probably quite a few. Was lots of mining out that way. I'm sure not many were deep enough to be usable for energy storage, but I'm sure there are quite a few.
I like that in-depth mining knowledge is just a part of life in the YOU PEE.
Quote from: MrH on January 20, 2023, 07:25:20 AM
I like that in-depth mining knowledge is just a part of life in the YOU PEE.
:lol: Logging and mining...they're what made You Pee towns exist.
My town is where iron ore was "first" discovered by a white man in da You Pee in 1844. Just comes with the territory. I love exploring old mine stuff, lots to see.
mindat.org is a great reference if anybody is looking for an abandoned mine/shaft near them.
Quote from: giant_mtb on January 19, 2023, 03:52:06 PM
Not possible. Below a certain level (depending on where you are, I guess) the shafts are constantly flooding. Massive, massive steam-powered pumps were used back in the day to keep the water out of the shafts. Same goes for modern open-pit mines...turn those pumps off and that pit very quickly becomes a small lake. Can't do this in an active mine.
Edit:
https://youtu.be/sDLpb6r80kA
Yep.
Pumping water out of mines is where the convention of using horsepower as a unit came from. Watts was selling steam pumping engines, and the most important economic factor was "how many horses would this replace?"
Also, him being from Cornwall and sending Cornish engineers out to install and run the engines is why there's still a large Cornish influence in the UP today.
Yezzir! The largest steam-powered pump ever built in the US was built here by the Corns. And is also why Cornish pasties are still seen as some sort of delicacy up here.
https://menomineemuseum.com/cornish-pump-museum
Talked to a friend of mine that used to drive truck in this mine. He said "always wet, pumps were always running, when I quit there we were at about 3,000' under, was a 4 mile drive to get in or out."
https://youtu.be/VITSTMQxwdQ
[/hack]
Hmmm. At first glance seems interesting, particularly there are no batteries, but putting some numbers to it:
A 1,000,000 kg weight (a 15' cube of lead) moving at 1 m/s generates 10 mW of power, or about as much as the largest wind turbine. Say that the shaft is 1000 m deep - that's 16.7 minutes of power. To reset the system (raise the weight) say takes 1% of the power (13,400 hp) which at 0.10 m/sec = 167 minutes, so for continuous power output will require 10 systems. The whole system will be something like 70% efficient. So, to get a continues 10 mW of output, you'd need 7 mW reserve/system * 10 systems systems = 14 systems, or to provide the power reserve for a good size dam on the Columbia (Rocky Reach generates 1300 mW) you'd need 1300 mW/7 mw * 10 systems = 1,857 systems.
So, I think, like wind/solar/wave, at first blush it seems like a great idea, but on any sort of scale, it becomes unrealistic, esp. the fossil fuels to dig the shafts and mine/refine/process the steel and copper, let alone the shear cost and socio-political turmoil of wrenching those elements out Africa and South America.
Quote from: giant_mtb on January 19, 2023, 03:52:06 PM
Not possible. Below a certain level (depending on where you are, I guess) the shafts are constantly flooding. Massive, massive steam-powered pumps were used back in the day to keep the water out of the shafts. Same goes for modern open-pit mines...turn those pumps off and that pit very quickly becomes a small lake. Can't do this in an active mine.
My sis used to be on the executive team for a big mining corporation. Part of her compulsory orientation training was flying her to South Africa and taking her into one of their deep level mines - miles down then more miles to the working faces. If you fell off the duckboards down there you were literally in hot water. Some kind of insane AC refrigeration system made it bearable. The idea was that people sitting in the HQ offices, up high in the company, should never forget the worker-bees at the sharp end - toiling away in steam oven conditions.
Quote from: Morris Minor on January 20, 2023, 11:43:54 AM
My sis used to be on the executive team for a big mining corporation. Part of her compulsory orientation training was flying her to South Africa and taking her into one of their deep level mines - miles down then more miles to the working faces. If you fell off the duckboards down there you were literally in hot water. Some kind of insane AC refrigeration system made it bearable. The idea was that people sitting in the HQ offices, up high in the company, should never forget the worker-bees at the sharp end - toiling away in steam oven conditions.
That's so cool. And also fair. Despite mining being very modern and bearable, it's still hard fuckin' work down there in the depths of it. There's a reason those people get paid well and also hate their jobs.
Quote from: Soup DeVille on January 20, 2023, 07:54:54 AM
Yep.
Pumping water out of mines is where the convention of using horsepower as a unit came from. Watts was selling steam pumping engines, and the most important economic factor was "how many horses would this replace?"
Also, him being from Cornwall and sending Cornish engineers out to install and run the engines is why there's still a large Cornish influence in the UP today.
Professor Soup strikes again.
Quote from: Soup DeVille on January 20, 2023, 07:54:54 AM
Yep.
Pumping water out of mines is where the convention of using horsepower as a unit came from. Watts was selling steam pumping engines, and the most important economic factor was "how many horses would this replace?"
Also, him being from Cornwall and sending Cornish engineers out to install and run the engines is why there's still a large Cornish influence in the UP today.
Cornwall? Scotts would disagree.
In HS (1992) I visited a TRONA mine near Green River, WY. Deeper down than the Empire state building is tall. They ring the elevator bells differently for equipment than people (more gradual acceleration/deceleration) and the elevator is big enough for vehicles/ big carts of product.
They used hydrogen-powered bonafide Jeeps (no roofs, windshield, doors) because of emissions. They excavate in a weird grid pattern then also attach anchors inside the pattern to make sure the tunnels don't collapse.
Biggest deposit of trona in the world, used for all sorts of manufacturing.
Above ground you'd never know it wasn't anything but Wyoming desert.