4 ms·
It is ridiculously uneconomical to create the volume for pumped storage. For context, with 100 meters of pressure head, you'd need 25,000 olympic swimming pools
by jjk166 4y ago
It is ridiculously uneconomical to create the volume for pumped storage. For context, with 100 meters of pressure head, you'd need 25,000 olympic swimming pools worth of water to store 12 hours of electricity from a 1 GW electric plant with 70% roundtrip efficiency. At a cost of $216/cubic yard of excavation, that's over $17 Billion. If you can make 3 cents per kwh profit buying at low times and selling at high, it would take 129 years to cover just the costs of digging the hole at the high spot. Then you need to dig another hole of the same size at the low spot so you can reuse the water.
There are really only 3 options - dam up a watershed so you can get a huge volume without much structure, build your resevoir on top of a mountain so you can get much larger pressure head and thus require less volume, or reuse a hole you were digging anyways such as an open pit mine. In all three cases you are heavily constrained by geography.
- whatshisface 4y agoIt is a good thing then that nature has already done the excavation for us by providing high and low spots.
- jjk166 4y agoYep, now we just need to excavate the reservoirs on those high and low spots, a mere 100% of the work required.
- brianwawok 4y agoThis is nonsense. We have lakes already. We don’t dig two giant holes in rock. Look at real work pumped storage costs.
- int_19h 4y agoThat's the "geographically dependent" part.
- pencilguin 4y agoExcept, not.
- int_19h 4y agoLakes aren't geographically dependent?
- pencilguin 4y agoDon't need any lakes.
- int_19h 4y agoMind the thread context. "This is nonsense. We have lakes already."
- pencilguin 4y agoMaybe you could read up, instead of guessing. Dikes are a technology older than writing.
- fastaguy88 4y agoI am curious where the 216/yd cost comes from. I had a rock driveway put in at 10/yd, and I assume the stone was excavated from somewhere.
- Kubuxu 4y agoUsually the rock is waste from excavation. When buying it you pay the cost of transport, group that did the excavation might have even paid for the rock to be removed.
- im3w1l 4y agoExcavating a circle of area A costs O(A). Building a wall around a circle of area A costs O(A^0.5).
- idiotsecant 4y agoI think you'll find the attached link is project currently in development that does exactly what you're saying is economically impossible. It clearly is not impossible to build a relatively shallow dikes on top of a butte.