17 ms·

Can someone explain why this is better than just using pumps to pump water up from the reservoir and extract the energy with when the water returned back?

• reincarnate0x14 5y ago
  It's not, but it doesn't require a giant reservoir next to a 100m+ elevation change. Almost all of the really good locations for dams already have them, and their water discharge rates are driven by a lot more than just power generation.
• tristor 5y ago
  It requires less surface area, both due to compressibility and due to hydrodynamics. Additionally, water is a strong erosion source, air is not, so this can make use of existing excavations much easier and deep excavation is very very expensive.
  • Murkin 5y ago
    But they already fill the underground containers with water when there is low air pressure. (thats what the reservoir on top is, no?)
• hannob 5y ago
  Pumped water only works if you have the right conditions. I.e. you need a certain altitude difference and enough space to have an upper and a lower water storage facility. Pumped water storage is very efficient and an established technology, so when it's possible it's a good choice, but it's not possible everywhere.
  • Murkin 5y ago
    From what I gather in their explanation, they use air pressure to push water out of an underground container. The energy is reclaimed when the pressure is released (i.e. water can fall back and fill the container). How is the energy density different that what is provided by the water's static energy due to gravity?
• buryat 5y ago
  not a lot of places have enough terrain to create a lake, plus in some places there's already shortage of water so removing it from usage would be pretty bad
  • Murkin 5y ago
    They have a large water reservour in their plan..