going offshore

Offshore wind energy is booming, with for once the UK in the lead, having installed over 1000 Megawatts (MW) of offshore wind farm generation capacity. Denmark is second in the league table, with 640MW in place, followed by the Netherlands at 250MMW and Sweden at 164MW. But several other EU countries are moving ahead. Belgium, Finland and Ireland all have working offshore projects, while Germany has started up its first large offshore project – it wants 10,000 MW by 2020. France has announced 10 zones for offshore projects off its Atlantic and Mediterranean coasts – it wants to have 6,000MW in place by 2020. However the UK seems likely to stay in the lead – it aims to install up to 40,000MW by around 2020, maybe more.
That's not to say there have not been problems. Costs have risen, in part because of the increased cost of materials like steel, which in turns reflects the increased costs of conventional energy. And there have been teething problems with some of the designs. A minor fault in the design of the transitional piece which connects the tower to the monopile foundations of the newer machines has been detected, which has resulted in movement of a few centimetres in a number of turbines. Fortunately it is not thought that there is any safety risk or threat to service or output and it's evidently planned to deal with the as part of the usual rolling programmes of operation and maintenance, with any repairs that are necessary being carried out turbine by turbine, so that there should be no impact on the operation of the rest of the wind farm. The fault evidently does not effect earlier offshore designs.
Clearly issues like this will have to be taken into account in the design of new much larger 10MW machines now being developed. However, one of the newer designs, the 10MW SWAY floating turbine being developed in Norway, won't face quite the same problem – it's actually designed to tilt by 5–8 degrees in the wind.
Outside the EU, in 2009 China installed a 3MW offshore turbine, the first unit of a 100MW project. And, after nearly 10 years of sometimes heated debate, the Cape project off Nantucket Sound in New England has at last got the go ahead. It will be the USA's first offshore wind farm – with 130 turbines. But many others are being considered, including floating versions for use in deeper water. For example, researchers at the Worcester Polytechnic Institute (WPI) have a $300,000 grant from the US National Science Foundations for a three-year on floating wind turbine platforms.
The EU is of course well advanced in this field – with for example the Norwegian Sway device mentioned above, Statoil Hydro's Hywind and the UK's 10MW Nova project. There is also the novel floating Poseidon wave and wind platform system being developed in Denmark – a 10MW version is now planned.
But a report released by the US Dept of Energy in 2008, says the 28 US states that have coastlines consume about 80% of all the electricity the US produces, so maybe they'll have an incentive to push ahead too.
As in the EU, the idea of an offshore supergrid to link up offshore wind projects has also been mooted in the US. Researchers from the University of Delaware and Stony Brook University say that linking Atlantic Coast offshore wind parks with high-voltage direct current (HVDC) cables under the ocean would substantially smooth out the fluctuations. As a fix for intermittency, they say "transmission is far more economically effective than utility-scale electric storage".