Japan has converted all of their largest hydroelectric plants to pumped storage, as far as I can tell: https://en.wikipedia.org/wiki/List_of_power_stations_in_

Japan has converted all of their largest hydroelectric plants to pumped storage, as far as I can tell: https://en.wikipedia.org/wiki/List_of_power_stations_in_Japan https://en.wikipedia.org/wiki/List_of_power_stations_in_Japa... Presumably countries with a higher proportion of electricity from hydropower, like Canada and Brazil, could get even more out of this than Japan does in terms of stabilizing renewables.