Offshore wind turbines are a great idea. When wind farms are built in the sea, people cannot complain about their looks, noise or shaddows. They can also be more efficient, because the wind is not blocked by mountains, buildings or forests. However, the sea cannot be too deep, because wind turbines need foundations. Or do they? General Electric is partnering with marine architecture firm Glosten to build floating wind turbines.
Currently wind turbines can only be built in areas where the depth of the sea is no more than 60 metres. It is possible to build them in deeper waters, but it quickly becomes impractical. Offshore wind turbines can be much larger as their components do not need to be transported on narrow roads. Also, the winds in the open sea tend to be much stronger, which results in more efficient power production.
Now GE and Glosten are working on a floating wind turbine. The concept isn’t new, but what makes GE/Glosten project unique is the size of the turbines – they are thinking about a structure that would be 260 meters high. And making it float is not easy. Rogier Blom, a Senior Principal Engineer in Model-Based Controls and the project’s principal investigator, said: “Designing a floating turbine is like putting a bus on a tall pole, making it float and then stabilizing it while it interacts with wind and waves. Doing this well is both a design and controls challenge”. GE is going to design optimized controls that could enable future offshore turbines to be 35% lighter. This will aid their floatation as well as make erection of these structures less complicated.
The end result would be a floating 12 MW GE turbine, remaining stable thanks to Glosten’s tension leg platform technology. These turbines could be built in the areas where the depths are larger than 60 metres. This would significantly expand the potential of offshore wind power generation, because there would be many more areas where these wind farms could be built. GE is estimating that the potential of US offshore wind resources could be expanded to more than 7,000 TeraWatt hours (TWhs) per year. That is nearly double the total annual US energy consumption of 4,000 TWh. And, of course, this technology could be applied in many areas in the world, not just the US.
GE has a rich history in offshore wind turbines. For example its Haliade-X is the world’s most powerful offshore wind turbine built to date and it is also a relatively new project. GE is convinced that the industry is only now tapping into the full potential of renewable resources and offshore power generation.
Source: GE