Which again is nonsense as stated. The average world energy consumption is about 3 TW and gravity storages produce exactly zero and can meet no demand at all. 70 TWh would be enough to store about one day of global electricity consumption, for example to smooth out solar and wind.
I understand that but the statement 70 TWh is enough storage capacity to satisfy the world electricity demand makes no sense. Electricity demand is a power not an energy.
