[greendave]

Hydro _can_ be reliable. But out in the drought-prone west it has not been especially so. California generated 33GWh from large hydro in 2019 (14.6% of total production) vs. 15Gwh (7.5%) of total production in 2021. 2022 will likely be worse.

[elihu]

Hoover dam kind of gets hit twice; not only is there less water moving through the system, but they've let the water levels drop to the point where the energy they could get by running, say, three gallons of water through the system now requires them to use four gallons because the altitude difference is less. (I don't know what the exact numbers are.)