- As of 2010, 5.8% of power supply in the United States, projected 5.9% by 2035. Largest renewable source EEI, 40
How does it work?
- Water flow moves a primary mover such as a turbine or water wheel
- Run-of-the-river does not interfere with the flow of water; dammed hydropower involves blocking the water flow to constrict flow points (increasing pressure) and/or to build up hydrostatic head for more convenient timing
- Flow can be moderated with sluice gates
Hydro and storage
- One of the oldest forms of energy storage is behind a dam– including using the energy of water flow at times where capacity is higher than demand to pump water back up into a reservoir