7 ms·

The heavy iron ore is essentially a large battery storing gravitational energy. In a way it's just another natural energy source. Maybe in the future clean powe

The heavy iron ore is essentially a large battery storing gravitational energy. In a way it's just another natural energy source. Maybe in the future clean power can be generated from pulling down mountains.

sigstoat 5y ago
> Maybe in the future clean power can be generated from pulling down mountains. it takes a lot of power to dismantle mountains and load them onto trains. and folks get real grumpy about mining operations leveling off mountains.
- _carbyau_ 5y ago
  And it sounds like a rather visible ... race to the bottom, as it were. :-)
perihelions 5y ago
>Maybe in the future clean power can be generated from pulling down mountains. With added bonus efficiencies from combusting the coal that fortuitously falls out!
deleted 5y ago
[deleted]
lwansbrough 5y ago
This idea is sort of being explored already: https://www.youtube.com/watch?v=itbwXMMkBQw https://www.youtube.com/watch?v=itbwXMMkBQw There's other ways of doing this too. Rolling a ball up a hill, inflating a balloon under water, etc.
- spurgu 5y ago
  That looks like a real life battery level indicator.
  - quickthrower2 5y ago
    My take: it's cheating at jenga.
mdeeks 5y ago
Apparently there is already the concept of rail train batteries: https://www.vox.com/2016/4/28/11524958/energy-storage-rail https://www.vox.com/2016/4/28/11524958/energy-storage-rail You run the trains up the hill when energy is cheap or, for example, when the sun is out and solar works. Then when you need it, you run the trains down hill to generate electricity. Similar to pumped hydro where they do the same by pumping water up hill and then draining it downhill later. Super cool!
- bodyfour 5y ago
  It's interesting as a thought, but I don't think it's likely to be large-scale practical. Suppose you wanted to run a normal electric train up a mountain. It would certainly take a decent amount of power but not so much that it would be a big challenge for a city-scale power grid. So far you're not yet talking the scale of power where storing it would really be interesting to a grid. One option to store more power would be to make the train much, much heavier. Sounds simple enough -- fill all of the cars with concrete and now hauling it up the mountain will store a lot more power. However now the rails and the trains themselves will need to be far sturdier than a normal railway, and will wear out quickly. The other option will be to simply scale up -- start the day with a hundred trains in a rail yard at the bottom of the mountain and over the course of a day move them all to a rail yard at the top. Now you have successfully stored a decent amount of juice. But hold on a minute... you've now built two large rail yards, meaning you'll need a lot of relatively flat real estate at both altitudes. How about instead you just dig a hole on each side, called it a reservoir, and put a pipe between the two? Certainly it must be a lot easier to store and move mass in the form of water than it is in the form of trains! That is why I don't see much potential in rail-based storage: if you have the geography to build one at-scale, probably you could build pumped hydro there cheaper. Even if you were in a water-scarce area where you would need to enclose both reservoirs to avoid evaporation loss it still sounds simpler to me than building and maintaining a hundred heavy trains would be. Also, routing a pipe between two reservoirs is a lot more flexible than building a railway.
  - mdeeks 5y ago
    Yeah the idea is the trains are filled with tons of weight. In my head it still seems like it would be cheaper than digging out massive reservoirs for pumped hydro. Rail seems relatively cheap even if you do have to replace it regularly because of the wear. It also seems like you could put the rail in all sorts of geographies, big and small. Maybe it isn't worth it unless you go big though... and at that point why not hydro. It's good questions though. No idea how the economics of it will work out vs pumped hydro.
codeismath 5y ago
Years ago I visited the Seneca Pumped Storage Generating Station [0] reservoir in person. It's a massive man-made lake on the top of a small mountain in Pennsylvania, USA. They pump water up to it at night (when there is excess energy in the power grid), and let the water out in the day when the demand for energy is high (turning some turbines on its way down). Prior to visiting I had an intellectual understanding of the concept of pumped storage [1], but I have to admit that it's one heck of an experience when you see it up close and personal. My thoughts standing at the edge of this massively perfect-circle deep lake full of water: "somebody built that... and it's one BIG BATTERY". If you get a chance to visit one of these, I highly recommend it! [0] https://en.wikipedia.org/wiki/Seneca_Pumped_Storage_Generating_Station https://en.wikipedia.org/wiki/Seneca_Pumped_Storage_Generati... [1] https://en.wikipedia.org/wiki/Pumped-storage_hydroelectricity https://en.wikipedia.org/wiki/Pumped-storage_hydroelectricit...
- breck 5y ago
  Interesting. The first thought that comes to mind when I see that circle is Apple HQ.
  - codeismath 5y ago
    I just measured on Google Maps: Apple HQ - around 1,600ft diameter Seneca Pumped Storage Lake: around 2,400ft diameter
- AdamJacobMuller 5y ago
  > one BIG BATTERY > The power plant, rated at 451 MW That's a damn big battery. I love pumped storage, too bad it's not used more.
  - AceJohnny2 5y ago
    > I love pumped storage, too bad it's not used more Pumped storage is awesome and the most cost-efficient way to store energy. It's used as much as possible, but... I attended a USGS [1] talk about dams (in California) a few years ago. The key takeaway is: all places worth damming have been dammed. There are no more dammable places, hydrologically and geologically speaking. When I drive through the central valley, I see a lot of roadside signs about "build more dams!" It's sad to see the miscommunication... [1] https://www.usgs.gov/science-support/communications-and-publishing/public-lecture-series https://www.usgs.gov/science-support/communications-and-publ... (I cannot immediately find a link to the specific talk. USGS is fun: full of crusty geologists, who even in the heart of the Silicon Valley aren't particularly technologically sophisticated (a nice reminder of how niche we all are) )
jvanderbot 5y ago
A thousand (1e3) metric tons (1e3 kg) of anything, up a thousand meters (1e3), has 1e9x(10)=1e10 Joules of potential energy on earth (g=~10 m/s2). At 80% conversion (8e9 J) and assuming 1/8 of the energy is "payload" after paying for the train to go up, that's still ~1e9 or a GigaJoule. At a -20% grade, you're looking at a 5km train ride, which reasonably might take a half hour or less (1800s). So, you're generating GJ/1800s = 555 KW by pulling down the mountain, assuming the rocks magically teleport into and out of your hoppers. (Thanks @calvinlh ) That's approximately 100-200 households per train pair, which might generate 10 K$ / month in electrical sales?
- r00fus 5y ago
  This would make for a great oatmeal comic material.
- calvinlh 5y ago
  You're off by a factor of 3600-- 1 watt is a Joule/second, not a Joule/hour. 1 GJ / 1800s ~= 555kW, not 2GW.
  - jvanderbot 5y ago
    I knew it seemed high. The GW description didn't match the wikipedia article.
- bigiain 5y ago
  A 20% grade is probably unachievably steep for ordinary railways. Even a 5% grade is considered remarkable. Wikipedia says (https://en.wikipedia.org/wiki/Saluda_Grade https://en.wikipedia.org/wiki/Saluda_Grade): Saluda Grade is the steepest standard-gauge mainline railway grade in the United States.[1] Owned by the Norfolk Southern Railway as part of its W Line, Saluda Grade in Polk County, North Carolina, gains 606 feet (185 m) in elevation in less than three miles between Melrose and Saluda. Average grade is 4.24 percent for 2.6 miles (4.2 km) and maximum is 4.9% for about 300 feet (91 m). Unless you're gonna build that mountain style with gear drive and toothed tracks, you're probably looking at 5% grade and a 20km ride, which drops you down to ~140kW for 2 hours. Ion the other hand, it seems you can get 11 thousand tonnes in a coal train: https://www.australianmining.com.au/news/%E2%80%8Bnew-coal-train-record-set-2/ https://www.australianmining.com.au/news/%E2%80%8Bnew-coal-t... So on my 5% grade track I could get 1.5MW and if you can get your 20% grade to work that'd be just over 6MW
hardwaregeek 5y ago
Energy Vault is a startup that stores energy using big concrete blocks. Pretty close to your idea: https://en.wikipedia.org/wiki/Energy_Vault https://en.wikipedia.org/wiki/Energy_Vault
usrusr 5y ago
Melting down glaciers that subsequently pass through turbines on the way down should come close enough I guess? That future is here.
slipframe 5y ago
Clean power and mountaintop removal are mutually exclusive. That is neither clean nor renewable. Among other things, the water that flows through mineshafts, collects in quarries, or over strip-mines is often toxic as hell. When you dig into the rock like that, you expose a lot of water soluble toxic shit to the elements which poisons everything downstream.
darig 5y ago
> Maybe in the future clean power can be generated from pulling down mountains. why do you think mars is mostly flat?
altitudinous 5y ago
A similar concept is the Snowy Hydro project in Australia - essentially it is a battery for clean energy generators such as wind and solar when they cannot generate. There are two lakes - one at the top of a mountain and one at the bottom. When the wind is blowing or the sun is shining the wind generators and the solar panels power pumps that pump water from the bottom lake up to the top lake. When the sun is down or the wind is not blowing and electricity cannot be generated from panels or wind, water is run using gravity from the top lake to the bottom lake through a turbine, generating electricity that way and ensuring constant supply.
dahfizz 5y ago
Literally destroying a mountainous environment is not clean energy.
- beerandt 5y ago
  But endless fields of solar panels and wind turbines is? That seems like a somewhat arbitrary, fine line to walk.
  - sigstoat 5y ago
    neither of them strike me as great but taking down the solar farm is probably cheaper and easier than rebuilding a mountain.
  - dahfizz 5y ago
    Those sources of energy are both renewable and can be deconstructed with no permanent environmental impact, which makes them "clean" in my mind but I agree it's an ambiguous word.
deleted 5y ago
[deleted]
Gravityloss 5y ago
Scifi novel idea: A habited planet without a sun (these actually exist) with heavy elements and high gravity. The surface unevenness is the best source of energy. After millions of years of extracting energy from flattening, the planet becomes a perfect ball and all life ceases as there is no energy to be found anywhere.
- samus 5y ago
  Geothermal energy is the way to go for this kind of worlds.
  - Gravityloss 5y ago
    If there is a live core.
kzrdude 5y ago
The iron ore was pulled up from the ground, so "some" energy is used there, to lift it into the trains. Now the mine is not quite as deep as ocean level, so there is still a net potential energy gain (you could say).

sigstoat 5y ago

> Maybe in the future clean power can be generated from pulling down mountains. it takes a lot of power to dismantle mountains and load them onto trains. and folks get real grumpy about mining operations leveling off mountains.

_carbyau_ 5y ago
And it sounds like a rather visible ... race to the bottom, as it were. :-)

perihelions 5y ago

>Maybe in the future clean power can be generated from pulling down mountains. With added bonus efficiencies from combusting the coal that fortuitously falls out!

deleted 5y ago

[deleted]

lwansbrough 5y ago

This idea is sort of being explored already: https://www.youtube.com/watch?v=itbwXMMkBQw https://www.youtube.com/watch?v=itbwXMMkBQw There's other ways of doing this too. Rolling a ball up a hill, inflating a balloon under water, etc.

spurgu 5y ago
That looks like a real life battery level indicator.
- quickthrower2 5y ago
  My take: it's cheating at jenga.

mdeeks 5y ago

Apparently there is already the concept of rail train batteries: https://www.vox.com/2016/4/28/11524958/energy-storage-rail https://www.vox.com/2016/4/28/11524958/energy-storage-rail You run the trains up the hill when energy is cheap or, for example, when the sun is out and solar works. Then when you need it, you run the trains down hill to generate electricity. Similar to pumped hydro where they do the same by pumping water up hill and then draining it downhill later. Super cool!

bodyfour 5y ago
It's interesting as a thought, but I don't think it's likely to be large-scale practical. Suppose you wanted to run a normal electric train up a mountain. It would certainly take a decent amount of power but not so much that it would be a big challenge for a city-scale power grid. So far you're not yet talking the scale of power where storing it would really be interesting to a grid. One option to store more power would be to make the train much, much heavier. Sounds simple enough -- fill all of the cars with concrete and now hauling it up the mountain will store a lot more power. However now the rails and the trains themselves will need to be far sturdier than a normal railway, and will wear out quickly. The other option will be to simply scale up -- start the day with a hundred trains in a rail yard at the bottom of the mountain and over the course of a day move them all to a rail yard at the top. Now you have successfully stored a decent amount of juice. But hold on a minute... you've now built two large rail yards, meaning you'll need a lot of relatively flat real estate at both altitudes. How about instead you just dig a hole on each side, called it a reservoir, and put a pipe between the two? Certainly it must be a lot easier to store and move mass in the form of water than it is in the form of trains! That is why I don't see much potential in rail-based storage: if you have the geography to build one at-scale, probably you could build pumped hydro there cheaper. Even if you were in a water-scarce area where you would need to enclose both reservoirs to avoid evaporation loss it still sounds simpler to me than building and maintaining a hundred heavy trains would be. Also, routing a pipe between two reservoirs is a lot more flexible than building a railway.
- mdeeks 5y ago
  Yeah the idea is the trains are filled with tons of weight. In my head it still seems like it would be cheaper than digging out massive reservoirs for pumped hydro. Rail seems relatively cheap even if you do have to replace it regularly because of the wear. It also seems like you could put the rail in all sorts of geographies, big and small. Maybe it isn't worth it unless you go big though... and at that point why not hydro. It's good questions though. No idea how the economics of it will work out vs pumped hydro.

codeismath 5y ago

Years ago I visited the Seneca Pumped Storage Generating Station [0] reservoir in person. It's a massive man-made lake on the top of a small mountain in Pennsylvania, USA. They pump water up to it at night (when there is excess energy in the power grid), and let the water out in the day when the demand for energy is high (turning some turbines on its way down). Prior to visiting I had an intellectual understanding of the concept of pumped storage [1], but I have to admit that it's one heck of an experience when you see it up close and personal. My thoughts standing at the edge of this massively perfect-circle deep lake full of water: "somebody built that... and it's one BIG BATTERY". If you get a chance to visit one of these, I highly recommend it! [0] https://en.wikipedia.org/wiki/Seneca_Pumped_Storage_Generating_Station https://en.wikipedia.org/wiki/Seneca_Pumped_Storage_Generati... [1] https://en.wikipedia.org/wiki/Pumped-storage_hydroelectricity https://en.wikipedia.org/wiki/Pumped-storage_hydroelectricit...

breck 5y ago
Interesting. The first thought that comes to mind when I see that circle is Apple HQ.
- codeismath 5y ago
  I just measured on Google Maps: Apple HQ - around 1,600ft diameter Seneca Pumped Storage Lake: around 2,400ft diameter
AdamJacobMuller 5y ago
> one BIG BATTERY > The power plant, rated at 451 MW That's a damn big battery. I love pumped storage, too bad it's not used more.
- AceJohnny2 5y ago
  > I love pumped storage, too bad it's not used more Pumped storage is awesome and the most cost-efficient way to store energy. It's used as much as possible, but... I attended a USGS [1] talk about dams (in California) a few years ago. The key takeaway is: all places worth damming have been dammed. There are no more dammable places, hydrologically and geologically speaking. When I drive through the central valley, I see a lot of roadside signs about "build more dams!" It's sad to see the miscommunication... [1] https://www.usgs.gov/science-support/communications-and-publishing/public-lecture-series https://www.usgs.gov/science-support/communications-and-publ... (I cannot immediately find a link to the specific talk. USGS is fun: full of crusty geologists, who even in the heart of the Silicon Valley aren't particularly technologically sophisticated (a nice reminder of how niche we all are) )

jvanderbot 5y ago

A thousand (1e3) metric tons (1e3 kg) of anything, up a thousand meters (1e3), has 1e9x(10)=1e10 Joules of potential energy on earth (g=~10 m/s2). At 80% conversion (8e9 J) and assuming 1/8 of the energy is "payload" after paying for the train to go up, that's still ~1e9 or a GigaJoule. At a -20% grade, you're looking at a 5km train ride, which reasonably might take a half hour or less (1800s). So, you're generating GJ/1800s = 555 KW by pulling down the mountain, assuming the rocks magically teleport into and out of your hoppers. (Thanks @calvinlh ) That's approximately 100-200 households per train pair, which might generate 10 K$ / month in electrical sales?

r00fus 5y ago
This would make for a great oatmeal comic material.
calvinlh 5y ago
You're off by a factor of 3600-- 1 watt is a Joule/second, not a Joule/hour. 1 GJ / 1800s ~= 555kW, not 2GW.
- jvanderbot 5y ago
  I knew it seemed high. The GW description didn't match the wikipedia article.
bigiain 5y ago
A 20% grade is probably unachievably steep for ordinary railways. Even a 5% grade is considered remarkable. Wikipedia says (https://en.wikipedia.org/wiki/Saluda_Grade https://en.wikipedia.org/wiki/Saluda_Grade): Saluda Grade is the steepest standard-gauge mainline railway grade in the United States.[1] Owned by the Norfolk Southern Railway as part of its W Line, Saluda Grade in Polk County, North Carolina, gains 606 feet (185 m) in elevation in less than three miles between Melrose and Saluda. Average grade is 4.24 percent for 2.6 miles (4.2 km) and maximum is 4.9% for about 300 feet (91 m). Unless you're gonna build that mountain style with gear drive and toothed tracks, you're probably looking at 5% grade and a 20km ride, which drops you down to ~140kW for 2 hours. Ion the other hand, it seems you can get 11 thousand tonnes in a coal train: https://www.australianmining.com.au/news/%E2%80%8Bnew-coal-train-record-set-2/ https://www.australianmining.com.au/news/%E2%80%8Bnew-coal-t... So on my 5% grade track I could get 1.5MW and if you can get your 20% grade to work that'd be just over 6MW

hardwaregeek 5y ago

Energy Vault is a startup that stores energy using big concrete blocks. Pretty close to your idea: https://en.wikipedia.org/wiki/Energy_Vault https://en.wikipedia.org/wiki/Energy_Vault

usrusr 5y ago

Melting down glaciers that subsequently pass through turbines on the way down should come close enough I guess? That future is here.

slipframe 5y ago

Clean power and mountaintop removal are mutually exclusive. That is neither clean nor renewable. Among other things, the water that flows through mineshafts, collects in quarries, or over strip-mines is often toxic as hell. When you dig into the rock like that, you expose a lot of water soluble toxic shit to the elements which poisons everything downstream.

darig 5y ago

> Maybe in the future clean power can be generated from pulling down mountains. why do you think mars is mostly flat?

altitudinous 5y ago

A similar concept is the Snowy Hydro project in Australia - essentially it is a battery for clean energy generators such as wind and solar when they cannot generate. There are two lakes - one at the top of a mountain and one at the bottom. When the wind is blowing or the sun is shining the wind generators and the solar panels power pumps that pump water from the bottom lake up to the top lake. When the sun is down or the wind is not blowing and electricity cannot be generated from panels or wind, water is run using gravity from the top lake to the bottom lake through a turbine, generating electricity that way and ensuring constant supply.

dahfizz 5y ago

Literally destroying a mountainous environment is not clean energy.

beerandt 5y ago
But endless fields of solar panels and wind turbines is? That seems like a somewhat arbitrary, fine line to walk.
- sigstoat 5y ago
  neither of them strike me as great but taking down the solar farm is probably cheaper and easier than rebuilding a mountain.
- dahfizz 5y ago
  Those sources of energy are both renewable and can be deconstructed with no permanent environmental impact, which makes them "clean" in my mind but I agree it's an ambiguous word.

deleted 5y ago

[deleted]

Gravityloss 5y ago

Scifi novel idea: A habited planet without a sun (these actually exist) with heavy elements and high gravity. The surface unevenness is the best source of energy. After millions of years of extracting energy from flattening, the planet becomes a perfect ball and all life ceases as there is no energy to be found anywhere.

samus 5y ago
Geothermal energy is the way to go for this kind of worlds.
- Gravityloss 5y ago
  If there is a live core.

kzrdude 5y ago

The iron ore was pulled up from the ground, so "some" energy is used there, to lift it into the trains. Now the mine is not quite as deep as ocean level, so there is still a net potential energy gain (you could say).