The first offshore floating wind turbine has been deployed off the coast of Brewer, Maine. The project, overseen by the University of Maineís Advanced Structures and Composites Center, is an early attempt to harness some of the strong offshore winds and paves the way for wind farms to be set up 50 miles off the coast where the winds are strong and consistent. Backers of offshore wind turbines believe they can harvest 5 gigawatts of power by 2030. (Source: University of Maine)
To my knowledge, Chuck, I don't think this is very far offshore, as in the photos of it deployed you can still see land. And apparently there are three concrete hulls that keep it stable rather than an anchor. This story has more details: http://bangordailynews.com/2013/06/13/news/hancock/umaines-floating-prototype-becomes-first-offshore-wind-turbine-to-provide-power-to-us/
Perhaps they should look at some of the offshore production platforms in the North Sea. They have used concrete there for many years. Some platforms float, but most anchor to the sea floor. They hold up well to storms.
I live at the coast and know how much energy potential there is in offshore winds. Projects like this are a good start to harnessing this energy to provide electricity, and I suspect it is the first of many similar efforts in the future. In fact, a Japanese company has built a wind turbine that also has a hybrid design to harvest ocean currents: http://www.designnews.com/author.asp?section_id=1386&doc_id=265402