The turbine inventor Henrik Stiesdal is small in the shadows of gigantic curves of steel, watching workers weld towers that will be rooted to the seabed. This factory in the Danish countryside has churned out thousands of masts for wind turbines whose blades can stretch more than 500 feet. It’s an important contribution to a global wind revolution that’s supplying electricity to millions of homes worldwide.
Soon the factory will set about a new task, manufacturing components for a different kind of turbine, designed by Stiesdal, that bobs on the open sea. These structures promise to put the strong, consistent gusts that blow over deep waters within reach for the first time. The turbines now found around Denmark, England, and the other coastlines of the North Sea are made for shallow water and require large underwater structures to fasten them in place. “Normal places don’t have shallow water near population centers—they have deep water,” says Stiesdal, a legendary turbine inventor and former executive at some of Europe’s biggest wind companies. This situation renders many coastal places unsuitable for wind power. “We could power California many times over with their offshore resource,” he says, “but it all has to be floating.”
At 63, Stiesdal has taken every step in the modern evolution of wind power. As a young man he designed the first turbine and later took part in the introduction of the first offshore wind farm, creating what’s now one of the fastest-growing forms of renewable energy. He’s seen global wind capacity grow from virtually nothing in 1978 to more than 600 gigawatts today, according to BloombergNEF data.
As 2019 ended, about three-quarters of global offshore capacity lay in Europe, mostly clustered around the U.K. and Germany. This regional dominance owes partly to the North Sea’s relative shallowness. Although similar waters off China, Vietnam, and the eastern U.S. seaboard could someday add more wind farms using established technology, there’s greater potential farther offshore. Many more places, including California, Japan, and South Korea, have heavy power needs, big ambitions to lower emissions, and deep seas. Not to mention that people tend to complain—loudly—about turbines within eyesight of the shore. The open sea isn’t in anyone’s backyard.