In October, employees at LM Wind Power’s wind turbine blade factory in Castellón, Spain, briefly left their posts to send off their biggest achievement to date — all 241 feet of it.
They sent the huge blade — four times longer than a bowling lane and the largest ever produced in Spain — to the local port, loaded it on a boat and shipped it to Germany, where it will harvest wind at the Merkur wind farm in the North Sea.
Bigger is better when it comes to wind turbines, especially those working offshore. Taller turbines with longer blades are able to reach higher into the sky, where winds are stronger and steadier. That makes them more efficient and able to generate more power more consistently. Turbines with long blades like those made by LM Wind Power, for example, generate about 100 times more power than their predecessors made in the 1980s, whose blades were more than four times shorter on average.
But bigger is also harder to build. Extra-large blades weigh more and require stronger and more flexible components to combat the heavier sustained winds offshore. The new LM Wind Power blades weigh 27 tons, even though they are hollow and the company makes them from a lightweight polyester fiber.
The blades are about 14 feet across at their widest spot near the base. Workers polish the blades’ sinuous, aerodynamic skin to precise specification so they can capture wind and turn the rotor even at lower wind speeds. The polishing takes place in a humidity- and temperature-controlled space because any variation in the surface can decrease the blade’s efficiency by as much as 2 percent.
Logistics is another stumbling block for the big blades. Transporting something nearly seven times longer than a telephone pole requires enormous preparation. Jose Luis Grau, LM Wind Power’s Castellón plant director, and his team spent 13 months working with state and local governments and the port authority to figure out how to move the first monster blade 29 miles from the factory to the port, located on Spain’s Mediterranean coast north of Valencia. Part of the preparation to get the blades to the port included removing lampposts and street signs, as well as paving throughways across roundabouts so the blades didn’t have to turn much.
But the trouble is worth it. Larger, more productive blades mean that wind farms will be able to generate the same amount of electricity with fewer turbines, making wind power more cost-effective. Wind power currently accounts for 11 percent of Europe’s electricity, and that number is expected to grow to 25 percent by 2030.
Although onshore wind farms are currently one of the cheapest ways in Europe to generate new power, offshore farms may be more flexible because they can grow to heights and scales impossible for their land-based cousins due to government height and noise restrictions and lack of available space. Plus, the wind offshore is simply better, in that it’s faster and more consistent.
Wind farm operators also have started adding sensors and software such as GE Digital’s Asset Performance Management (APM) system to make their turbines even more efficient. APM uses data analytics to spot potential problems sooner and allow maintenance workers to fix them before they get out of hand. GE estimates customers will pay 15 percent less in maintenance costs because of new features like real-time diagnostics, which can help them avoid the expense of sending large marine cranes to carry out repairs.
GE Renewable Energy acquired LM Wind Power earlier this year. The company makes blades for GE turbines as well as those made by other manufacturers.
It’s not just Europe that’s interested in wind power. Renewable energy capacity in the U.S. tripled this decade, mainly due to wind and solar power growth. As turbine blades continue to lengthen, driving down costs, expect to see more wind farms whipping up energy and savings around the globe.