The facility is sited adjacent to a wind farm and has a 25 MW / 100 MWh capacity (in other words, the facility can provide 25 MW of electricity to the grid for 4 hours at a time).
The speed seems to be far higher than the 2 m/s for ocean gravity storage (limited speed because of Archimedes’ buoyancy and hydro drag), leading to far higher power density, because kinetic energy increases by the square of the speed.