Off-shore wind power

The green light has been given for two offshore wind farms in the Thames Estuary, one of which will be the world's biggest when it is completed.

The government said the schemes would produce enough renewable electricity to power about one million households. The larger London Array project covers 90 sq miles (232 sq km) between Margate in Kent and Clacton, Essex.

The second wind farm, called the Thanet scheme, will cover 13.5 sq miles (35 sq km) off the north Kent coast.

The £1.5bn London Array scheme will have 341 turbines rising from the sea about 12 miles (20km) off the Kent and Essex coasts, as well as five offshore substations and four meteorological masts.

The consortium behind it is made up of Shell WindEnergy Ltd, E.ON UK Renewables and Core Ltd. The smaller £450m Thanet project will be located seven miles (11km) out from North Foreland, Kent, and will have 100 turbines.

Developed by Warwick Energy, it could be supplying electricity to about 240,000 homes by 2008.

The government said both schemes would make "a significant contribution to the aim of a five-fold increase in the UK's renewable energy resource by 2020".

Friends of the Earth said about 1% of electricity used in the UK would come from the London Array turbines.