Actually no, the current form of pumped storage is using electricity already produced by a hydro dam to spin the turbine backwards to pump water uphill.
That doesn't even make sense.
Some existing facilities do use pumps as generators and vice versa, but they aren't using hydro dam power to pump water uphill, they're using solar and wind generated electricity to drive the pumps. And they wouldn't be at hydroelectric generator dams, they'd be at things like open-pit mines that have been converted to storage reservoirs.
Using wind/solar is a new and more efficient approach since the station continues to send power to the grid.
This isn't actually new.
-k