(Fortune Magazine) -- It's been a century or so since Britain ruled the waves, but Queen Elizabeth II will soon reign over the wind. Earlier this year the Crown Estate, which manages royal property worth $14 billion and controls the seas up to 14 miles off the British coast, agreed to purchase - for an undisclosed sum - the world's largest wind turbine.

It's a 7.5-megawatt monster to be built by Clipper Windpower of Carpinteria, Calif. Now the Royal Turbine is getting even bigger: Clipper has revealed to Fortune that Her Majesty's windmill has been supersized to ten megawatts, producing five times the power generated by typical big turbines currently in commercial operation. The giant's wingspan stretches the length of two soccer fields. At 574 feet, the turbine soars over Big Ben and roughly equals 111 Queen Elizabeths (the actual queen) plus one corgi stacked on top of one another.

The Queen's turbine will displace two million barrels of oil as well as 724,000 tons of CO2 over its lifetime. This prototype will be the flagship for Clipper's Britannia Project, an effort to create a new generation of massive-megawatt turbines to be placed on deep-sea floating platforms. When the windmill goes online in 2012 somewhere off the British coast, it could power 3,700 average homes.

Rule, Britannia, indeed.