Comment by Retric

It’s not universal, smaller dams don’t have nearly as much storage as large ones but they also produce vastly less power. At the other end the Great Lakes are effectively storing years worth of electricity, and have significant flexibility in delivery.

Looking at the US most of it is family close to large scale hydropower, except Florida, but it’s a little under 7% of annual power nationwide. https://www.eia.gov/todayinenergy/images/2011.06.10/hydro_pa...