Wind turbines can rotate on either a horizontal or vertical axis. To date, there have not been too many deployments of vertical-axis wind turbines off-shore, they have tended to be use in more urban areas. However, Norway is home to a number of pilots testing various vertical axis designs off-shore, including this one. Benefits of this design include:-
- no need to track the wind
- maintenance is easier as all the gear is at the base of the tower, not the top
- can be placed closer together = more energy/less space
- reduced risk of bird strike
https://electrek.co/2023/01/27/norway-vertical-axis-floating-wind-turbine/