When people hear "floating wind turbines," they often think of the large-scale offshore wind farms that are already commonplace in some parts of the world.
But there's an important distinction.
While conventional offshore wind—in which the turbines are mounted in relatively shallow water and fixed to the sea floor—has scaled up considerably over the last few years, floating wind turbines—which are anchored using cables but do not have a fixed foundation on the sea floor—have so far only been deployed in small-scale trials.
That may be beginning to change. Given their potential to both drive down the cost of wind energy and increase the geographical range of feasible sites (floating turbines will be able to operate in much deeper waters than fixed-base turbines), wind energy advocates are beginning to look at larger scale deployment. So an announcement that Norway's Statoil has just gotten approval for the Hywind floating wind farm project off the coast of Scotland should be welcome news indeed.
Consisting of five, 6 MW floating turbines, Hywind is still pretty minuscule compared to the 10.6GW of offshore wind that the UK already has either operating or in the pipeline, but the fact that these turbines will operate in waters exceeding 100 meters in depth should give you some idea of why this matters. Given appropriate support and R&D, The Carbon Trust has estimated that floating turbines could provide 8 to 16GW of offshore wind capacity in the UK alone by 2050. The Trust also estimates that improvements in floating turbines could drive down the cost of production to below £100/MWh within a decade. (The cost for conventional offshore wind is something like £140/MWh right now.)
It's all pretty exciting stuff. Here's a little background on just some of what it's going to take to get things done.