2 ms·

This is not how it works. The dam in Oregon (or anywhere) doesn’t work on kinetic energy from the flow. In fact it often is stopping the flow (dissipating the k

• thaumasiotes 8y ago
  > The elevation drop that matters is from the top of the dam to the bottom of the dam. > Doesn’t matter a whit whether the water that falls that 500’ has previously come from 1000’ or 10,000’. Depends what you're counting. As you say, stopping the river entirely dissipates its accumulated flow. If you're downstream, then such a dam would lose you much more energy in the case where the water had originally come down 10,000' than in the case where it had originally come down 1,000'. The energy harvested usefully is the same, but the energy wasted is very different. And the total, the energy removed, is also very different. I'll note, though, that a dam that completely stops the flow of the river is producing zero energy. (And also, about to cause a flood somewhere.) You only get energy by letting water through, and slowing it while it goes.