THE NEW YORK TIMES
How Windmills as Wide as Jumbo Jets Are Making Clean Energy Mainstream
The biggest turbines in Osterild stretch more than 600 feet high.
The largest rotor blades can reach 270 feet in length, comparable to the wingspan of an Airbus A380, the world’s largest commercial plane. The price tag: Up to 10 million euros, or more than $12 million.
The monstrous scale has helped turn wind into a mainstream form of power.
Larger turbines harness more wind, creating more energy. The biggest modern offshore turbines produce nearly 20 times as much power as ones developed three decades ago.
Making these blades is difficult and labor-intensive.
Teams of workers gradually fill a mold with strips of fiberglass interlaced with balsa wood for strength. They then inject resins and other chemicals into the container to form the hardened structure.
The huge size of the blades, and the complexity of the process, mean completely automating it does not make economic sense.
Around 1,300 people work in the factory, and making a single blade can take about three days.
It’s a difficult balance for manufacturers to achieve both size and efficiency. The largest blades already weigh around 30 metric tons, and making them longer adds to their weight, fast.
Overweight blades might lead to turbines being worn down faster, and would put enormous stress on other components.
In the early years, building an offshore wind farm was fantastically expensive, and governments offered generous subsidies to help the industry develop. But prices have been falling, and government support has “melted away,” according to Andreas Nauen, the chief executive of Siemens Gamesa’s offshore wind division.
Lower costs, though, have also made wind power more appealing elsewhere. Once mostly concentrated in northern Europe, Mr. Nauen is optimistic that new markets will emerge in Asia and the United States.
“This is real,” he said.
https://www.nytimes.com/interactive/2018/04/23/business/energy-environment/big-windmills.html
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