@rwg Itâs a historical thing - most electricity was generated via Hydroelectric power - it became shorthand for all things relating to the electric grid. âTheyâre repairing the hydro linesâ would make perfect sense, even though they werenât talking about water.
The term has persisted, even though Ontarioâs power is largely nuclear now. In Quebec, âHydro Quebecâ makes more sense since around 90% of their generating capacity comes from hydroelectric generation.
Itâs just a strangely Canadian thing, like measuring driving distance in hours, or describing your height or weight in feet and pounds, but using metric for nearly everything else.
Having said all that, âHydro windmillsâ is weird. âWind turbineâ is probably better / more accurate.