5 ms·

Would it matter if it was containers filled with water, soil, trash instead?

by JudasGoat 8y ago

monochromatic 8y ago
Way less dense than concrete. So less energy stored.
- yummybear 8y ago
  Sand and water?
  - LeifCarrotson 8y ago
    Rock.
MauranKilom 8y ago
Aside from mass density, the problem here would be structural integrity. How high can you stack buckets of water before the tower collapses? Probably not 120 meters. It comes as no surprise to me that this would use the same kind of material as a 120 m tall "normal" building.
- CamperBob2 8y ago
  Considering that water isn't compressible, I'd think you could stack them even higher. Just use cylindrical containers with high strength in the radial direction. Also, how about compressing plain old air in an array of individual columns? It might be reasonable to improve the efficiency with some sort of heat exchanger.
  - MauranKilom 8y ago
    That would be a lot of steel. 100 meters of water is submarine territory. You need some thick walls to stem the radial pressure alone, probably at least 5 inches or 13 cm of steel (consider [0] and [1], this value also agrees with my intuition from engineering education). Assuming a barrel of 2 m radius and 3 m height (volume ~36 m³), that's 5 cubic meters (or 8 tons) of steel you'd need for the cylindrical hull alone, costing around 8000 USD in material [2] (varies wildly of course, but you're probably not using submarine grade steel). Per ~40 ton barrel. Would make about 40 million in steel costs alone for the number of barrels shown. I have no idea what your air compression idea entails, but it doesn't sound more realistic. Concrete is pretty good at being stacked (source: look around you). [0] http://www.madehow.com/Volume-5/Nuclear-Submarine.html http://www.madehow.com/Volume-5/Nuclear-Submarine.html [1] https://en.wikipedia.org/wiki/Submarine_hull#Dive_depth https://en.wikipedia.org/wiki/Submarine_hull#Dive_depth [2] https://www.wolframalpha.com/input/?i=steel+cost https://www.wolframalpha.com/input/?i=steel+cost
  - camtarn 8y ago
    Compressed air energy storage is also being investigated in a variety of forms: https://en.wikipedia.org/wiki/Compressed_air_energy_storage https://en.wikipedia.org/wiki/Compressed_air_energy_storage
CydeWeys 8y ago
They're not containers, they're structural. They need to be stackable dozens tall. You're basically limited to the kinds of materials you can build tall buildings out of -- concrete or steel. And concrete is much cheaper.

Would it matter if it was containers filled with water, soil, trash instead?

monochromatic 8y ago

Way less dense than concrete. So less energy stored.

yummybear 8y ago
Sand and water?
- LeifCarrotson 8y ago
  Rock.

MauranKilom 8y ago

Aside from mass density, the problem here would be structural integrity. How high can you stack buckets of water before the tower collapses? Probably not 120 meters. It comes as no surprise to me that this would use the same kind of material as a 120 m tall "normal" building.

CamperBob2 8y ago
Considering that water isn't compressible, I'd think you could stack them even higher. Just use cylindrical containers with high strength in the radial direction. Also, how about compressing plain old air in an array of individual columns? It might be reasonable to improve the efficiency with some sort of heat exchanger.
- MauranKilom 8y ago
  That would be a lot of steel. 100 meters of water is submarine territory. You need some thick walls to stem the radial pressure alone, probably at least 5 inches or 13 cm of steel (consider [0] and [1], this value also agrees with my intuition from engineering education). Assuming a barrel of 2 m radius and 3 m height (volume ~36 m³), that's 5 cubic meters (or 8 tons) of steel you'd need for the cylindrical hull alone, costing around 8000 USD in material [2] (varies wildly of course, but you're probably not using submarine grade steel). Per ~40 ton barrel. Would make about 40 million in steel costs alone for the number of barrels shown. I have no idea what your air compression idea entails, but it doesn't sound more realistic. Concrete is pretty good at being stacked (source: look around you). [0] http://www.madehow.com/Volume-5/Nuclear-Submarine.html http://www.madehow.com/Volume-5/Nuclear-Submarine.html [1] https://en.wikipedia.org/wiki/Submarine_hull#Dive_depth https://en.wikipedia.org/wiki/Submarine_hull#Dive_depth [2] https://www.wolframalpha.com/input/?i=steel+cost https://www.wolframalpha.com/input/?i=steel+cost
- camtarn 8y ago
  Compressed air energy storage is also being investigated in a variety of forms: https://en.wikipedia.org/wiki/Compressed_air_energy_storage https://en.wikipedia.org/wiki/Compressed_air_energy_storage

CydeWeys 8y ago

They're not containers, they're structural. They need to be stackable dozens tall. You're basically limited to the kinds of materials you can build tall buildings out of -- concrete or steel. And concrete is much cheaper.