There are floating wind farms. The world's largest (according to [0]) is due to be built off the north east coast of Scotland next year.
Incidentally, this is not far from the site of another offshore wind farm which a certain Donald Trump waged a lengthy legal battle to try to prevent, because he thought it would spoil the view from his golf course[1].
Bear in mind that you can already see large numbers of offshore oil rigs off the coast of parts of north east Scotland.
[0] https://www.theguardian.com/environment/2016/may/16/worlds-l...
[1] https://en.wikipedia.org/wiki/Trump_International_Golf_Club_...