The BBC’s online article “Offshore wind farms face uncertain future”
Atlantic Array’s 1.2GW was part of 32GW of planned offshore wind capacity
The article looks at the viability of offshore wind farms. While these are clearly more expensive to install and maintain, the challenges being not just the distance from port and dealing with the weather, but also establishing electrical connections, undersea cable and a link into the onshore grid, then there is the salt! Conversely, the wind is more consistent and with bigger turbines, far more capacity can be installed.
One of RWEs comments was that the project might be viable with the next round of technology, I guess both bigger turbines going up to 5MW capacity and maybe floating turbines that in extremis can come back to port to be maintained.
The idea of a tethered floating turbine, or maybe on jack-up type bases, using oil industry type technology must be an attractive alternative to static pin piled turbines? The advantages, with a working system would circumvent many of the current disadvantages. Both jack-up and floating/tethered can be fully fitted out in dock and potentially returned to dock for major refurbishment on a routine basis. Rather than having an installed turbine that degrades over the years to the point where it is fit for the scrap yard, along with the huge cost of dismantling, a portable wind turbine might go on for many decades.
In the case of non fixed turbines, I would tend towards vertical axis turbines. With a horizontal axis turbine there is always going to be a stress as the wind tends to push the turbine mountings over. A VAWT in spinning on a vertical axis will have a gyroscopic effect, aiding the stability of the installation. Agreed, the technology is in a sense still developing, but surely the ultimate benefits will seriously outweigh that additional cost of development, certainly more so than the current tendency towards what seems to me the brute force approach of ever bigger turbine blades with the concomitant problems of more bearing problems, bird strike, bigger foundations.