Energy Generation: Off Shore Wind Turbines

The first large scale offshore wind farm in the UK, North Hoyle, was commissioned in December 2003 and the second, Scroby Sands one year later in December 2004, followed by the world's largest offshore wind farm, the 90-MW (megawatt) Kentish Flats in 2005. Together with the Blyth Offshore pilot project this makes a total of 213.80 MW of offshore wind around the UK coast. But this is only the beginning.

Most modern offshore projects have been built with 2 - 3 megawatt machines, but in future this will rise to 3 - 5 MW. Higher wind speeds at sea mean an increased energy production. Each turbine would typically generate enough electricity each year to meet the needs of 2500 households while displacing in the region of 50,000 tonnes of carbon dioxide as it does so.

Offshore wind energy is expected to be a major contributor towards the Government's 2010 target for renewable generation, and is being taken increasingly seriously by the UK energy sector. Companies involved in the UK offshore market now include multinational energy and utility companies. There is 954 MW of projects with planning consent waiting to be built, and a second round of offshore tenders from the Crown Estate with a total of 7.2 GW (gigawatt) waiting for applications, equivalent to 7% of UK supply. In total offshore wind could contribute as much as 4% to the Government's 2010 targets for renewable energy.

The UK has potentially the largest offshore wind resource in the world, with relatively shallow waters and a strong wind resource extending far into the North Sea. The UK has been estimated to have over 33% of the total European potential offshore wind resource - enough to power the country nearly three times over.

Only a fraction of the UK seabed would be needed to house offshore turbines. Given that the offshore resource is so large, conservative estimates suggest that aside from economic constraints offshore wind alone could meet the Government target of 10% of all electricity generation from renewables by 2010. This would require 10 GW of turbines. Assuming a typical offshore turbine to be 3 MW, this translates to 3,300 turbines in an area of seabed 1,200 km2 - an area roughly the size of a city like London. If the UK were to match the more ambitious Danish plan and generate 40% of the country's electricity needs by 2030 offshore, then this equates to 48 GW from 16,000 turbines in an area roughly 4,800 km2 - less than 1% of the UK's seabed.

Should all the sites announced by the Crown Estate go-ahead, they will produce sufficient electricity to power over 4 million households.

For more details see http://www.bwea.com

NOTES:
The megawatt (symbol: MW) is a unit for measuring power equal to one million watts. Or enough to electricity to power 50 thousand x 20 watt low energy light bulbs.

The gigawatt (symbol: GW) is a unit for measuring power equal to one billion watts. Or enough to electricity to power 50 million x 20 watt low energy light bulbs.