Ffestiniog Power Station in the UK is on the order of 1 hectare (1/100 km^2) in area (based on 170,000 m^3 storage and a 34m dam height). It's a modest and early pumped-hydro facility.
https://en.wikipedia.org/wiki/Ffestiniog_Power_Station
Bath County Pumped Storage in the US has an upper reservoir of 107 and a lower of 226 hectares respectively, or 1 km^2 and 2 km^2, roughly. It is the largest in the US.
https://en.wikipedia.org/wiki/Bath_County_Pumped_Storage_Sta...
There is no reason for a purely pumped-hydro facility to be anywhere remotely near the size of Itaipu. Which is not in fact a pumped hydroelectric storage facility, but a hydroelectric generating station with no pumped-hydro storage capabilities or functions.
https://en.wikipedia.org/wiki/Itaipu_Dam
A red herring.
>You couldn't be more Dam wrong.
I am talking about dams, not pumped storage.
And was followed up, by the same author, with another post specifically about pumped storage: https://news.ycombinator.com/item?id=21479576
That we're still discussing this over 24 hours later may strike someone as amusing, but the jokes gone rather stale.
Cheers.
Nothing. Was there something to suggest otherwise? I listed two weak points for hydro: Terrible energy density, massive land use.
My first reference supported the first point and my second reference addressed the second point. Land use: 1,350 square kilometres were flooded. The installed power was to give context of how big the plant is.