NZ Marine Energy Sites can be split into offshore wind, wave and tidal energy sites.
Offshore wind is generally very good on the West Coast of both Islands
This is the same for wave energy. The Cook Strait can get freak waves of up to 8 m.
Tidal energy sites include harbours like Hokianga, Whangarei and Kaipara Harbour in Tai Tokerau/ Northland, the Cook Strait, Queen Charlotte Sound, Foveaux Strait near Stewart Island.
Source: MetOcean, NIWA, Venture Taranaki.