On Thursday, the world’s largest offshore windfarm will open off the coast of northwest England. The wind farm, named Walney Extension, has a capacity of 659 megawatts (MW), enough to power almost 600,000 homes. The previously largest offshore windfarm was the London Array on England’s east coast which has a capacity of 630 MW.
Walney Extension is composed of 87 turbines built by Siemen Gamesa and MHI Vestas, and covers 145 square kilometers (55 square miles). The 40 eight-megawatt MHI Vestas turbines stand 195 meters tall and are the largest wind turbines in operation globally.
Britain’s success in offshore windfarms comes from a combination of strong wind speeds and shallow waters in the North Sea and Irish Sea as well as continued support from the government. For the last 10 years, UK governments have supported renewable energy and offshore wind, leading to a thriving industry. Britain is home to 36 percent of globally installed offshore wind capacity, according to data from the Global Wind Energy Council.
Walney Extension was one of the first renewable project to secure a contract for difference (CFD) subsidy from the British government in 2014, guaranteeing a minimum price for electricity of 150 pounds ($195) per megawatt hour (MWh) for 15 years.
Since the CFD subsidy was awarded, cost of offshore wind has fallen dramatically to a low of 57.50 pounds per MWh in the last auction held in 2017.