Where did you pull that from?
8GW could be done with a total of 620 offshore 13MW turbines.
GE claim capacity factor of 60-64%, which is lower to than Koebergs high 70%.
Koeberg on the other hand is 1.8GW. Apples to apples for 1.8GW you'd need 140 turbines. Or 165 turbines to be equivalent to the same capacity factor as Koeberg. 1km distance recommended distance turbine to turbine, so you wouldn't need that much space.
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