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Europe's deepest mine to become giant gravity battery

independent.co.uk

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Re: Europe's deepest mine to become giant gravity battery

#101

Post by concordDance »

undersuit wrote: post #53
bunabhucan wrote: post #26

>The decommissioning of mine shafts is a costly and time-consuming process for mining companies. I wonder if that is part of the impetus - make cleanup/decommissioning happen in distant future dollars helps the balance sheet today. https://www.marketscreener.com/quote/stock/ABB-LTD-9365000/n...

I think that the cost(or even profits) of filling a mine back in after excavation should be considered from the beginning. Hell we could even sell the futures now to recoup the cost of building a mine tomorrow.

Why do we want to fill them back in anyway? A new valley/hole doesn't seem like the biggest priority.

Re: Europe's deepest mine to become giant gravity battery

#102

Post by tialaramex »

onion2k wrote: post #65
undersuit wrote: post #53

Earlier quoted context omitted.

I think that the cost(or even profits) of filling a mine back in after excavation should be considered from the beginning. Hell we could even sell the futures now to recoup the cost of building a mine tomorrow.

Wouldn't that require knowing how far down/across you're going to dig? Most mines have a known seam to begin with, but a lot of exploration and geology work comes later when there's a big hole to work from. There's only so much you can tell at the surface before you start.

You can (and a less corrupt industrialized country's government sometimes will) require that they give you the money [or lock it into a fund they don't control] before they get permission to make the hole bigger. You need government inspections (so they can't make it bigger without permission) to make this possible, but those are needed for safety anyway.

If you let them, they'll eventually walk away leaving you with a toxic mess and a hole in your budget. The same thing applies for a government securing clean-up funding or a musician securing royalties from a label/ publisher, make sure you get paid first, if you're supposedly getting paid last it will always turn out that whoops, there is no money left, thanks for making us rich, bye.

Re: Europe's deepest mine to become giant gravity battery

#103

Post by donquichotte »

concordDance wrote: post #100
donquichotte wrote: post #88

Earlier quoted context omitted.

My thoughts exactly. It makes the engineer in me go mad if I see projects like Energy Vault [1] getting massive funding that could be used to try and develop technologies that make sense. Thankfully there are some people who see through the charade [2]. If you are into this thing and looking for an even more stupid idea to store energy, I present to you the StEnSEA [3]. Rolls right off the tongue, right? It is a holl…

> 3.8kWh That seems very low. Their website mentions 20 Mwh+. Though my back of the envelope agrees with yours.

If I understand it correctly, ~20MWh is for the full size model at 700m depth and with a radius of 15m (prototype radius is 1.5m and it is located at a depth of 100m).

And building concrete spheres that can withstand the pressure of a 700m water column is probably an interesting design challenge on its own.

Re: Europe's deepest mine to become giant gravity battery

#104

Post by danbruc »

TheOtherHobbes wrote: post #77
danbruc wrote: post #72

Earlier quoted context omitted.

Which again is nonsense as stated. The average world energy consumption is about 3 TW and gravity storages produce exactly zero and can meet no demand at all. 70 TWh would be enough to store about one day of global electricity consumption, for example to smooth out solar and wind.

That's why these projects are called batteries, not generators. The nuke and fossil lobbies make a big deal out of how renewables are intermittent, and this is one of many practical ways to fix that.

I understand that but the statement 70 TWh is enough storage capacity to satisfy the world electricity demand makes no sense. Electricity demand is a power not an energy.

Re: Europe's deepest mine to become giant gravity battery

#105

Post by danbruc »

usrusr wrote: post #98
alvah wrote: post #29

Earlier quoted context omitted.

Allow me to support the completely unsupported naysaying: https://cleantechnica.com/2024/01/16/gravity-storage-101-or-... Cliff's Notes: any currently-considered form of gravity storage that isn't pumped hydro is orders of magnitude more expensive and more stupid than a Tesla Megapack. Michael Barnard's abrasive tone aside, is he wrong?

Nice hit piece that looks like written by someone deeply invested in chemical batteries (or going mercenary for patrons who are). But his dismissal of mine shafts omits some important parts: when you have a mine, you don't just dangle a mass from an elevator winch, you fill the entire volume at the low end with ballast while discharging and get all that mass up again when charging. That's a many orders of magnitude d…

Then why not pour water down the mine shaft and pump it back out? That seems a lot less complicated than transporting any kind of solid material up and down. I can think of three possible reasons - material density, loses in pumps and pipes, and potentially measure to make the mine suitable for storing water.

Re: Europe's deepest mine to become giant gravity battery

#107

Post by euroderf »

cderpz wrote: post #87
GuB-42 wrote: post #25

Isn't there a better article? - 2 MW of energy MW is a unit of power not energy, maybe they mean 2 MWh, but if that's the case, it is a joke. That's like 30 Teslas cars, or half of a Tesla Megapack, which is a shipping container sized battery. 2 MW of power is not that big either, that's about what you get from a typical wind turbine. - 70TWh of energy At least, we have a proper unit, but I wish they tell us a bit mo…

They probably mean 2MW peak output/input with the chain at maximum weight and velocity.

This would be a great plot element in a post-apocalypse film. Mad Max meets The Coal Miner's Daughter.

Re: Europe's deepest mine to become giant gravity battery

#108

Post by imtringued »

effie wrote: post #80

Another completely misleading article on gravity batteries. All the solid weight stuff is bunk, probably designed to suck out money from naive investors / corrupt state officials. Moving solid weights gives only a very small electric power, so building the proposed solid weight batteries gives units of MW at most, which is uneconomical. Unless it transports a large lake of water up and down a hill like in pumped-stor…

Gravity batteries are so appealing, until you calculate the cost per kWh. Any weight that you have to manufacture is already too expensive and you want manufactured weights since you want your weights to be as dense as possible and not just made out of compressed dirt.

Re: Europe's deepest mine to become giant gravity battery

#109

Post by usrusr »

danbruc wrote: post #105
usrusr wrote: post #98

Earlier quoted context omitted.

Nice hit piece that looks like written by someone deeply invested in chemical batteries (or going mercenary for patrons who are). But his dismissal of mine shafts omits some important parts: when you have a mine, you don't just dangle a mass from an elevator winch, you fill the entire volume at the low end with ballast while discharging and get all that mass up again when charging. That's a many orders of magnitude d…

Then why not pour water down the mine shaft and pump it back out? That seems a lot less complicated than transporting any kind of solid material up and down. I can think of three possible reasons - material density, loses in pumps and pipes, and potentially measure to make the mine suitable for storing water.

That's what GP suggested. But unless the mine happens to be in particularly water-friendly rock or is carefully prepared for safe repeated flooding/dewatering, that would only speed up the conversion from mine to uncontrolled sinkhole. Many given up mines are expected to have active dewatering running forever, because the cost of letting them collapse or for safe filling would be so much greater than the cost of continued dewatering for the next couple of generations.

For small capacities, using water as the ballast medium would certainly be cheaper. But there's a break-even point in capacity beyond which the cost for readying the volume for water would be higher than the premium you'd have to pay for handling dry mass instead of liquid.

Re: Europe's deepest mine to become giant gravity battery

#110

Post by usrusr »

usrusr wrote: post #97
8bitsrule wrote: post #70

Earlier quoted context omitted.

Here in the PNW, "The Columbia River Gorge is a canyon ... up to 4,000 feet (1,200 m) deep [and which] stretches for over eighty miles (130 km) as the river winds westward [toward Portland]." - WPedia Hmmm. Now I'm wondering how many reservoirs already (or could) exist above and along 80 miles of river. (No need to dig tunnels to the generators.)

Exactly one reservoir (or a number of tiny ones not worth mentioning), because even all the way from Richland to Portland there is hardly any elevation drop.

PS: oh, you meant reservoirs in contributory valleys left and right of the main river. Sorry about the misread, "above and along" should have been clear enough.
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