Some of the world’s top manufacturing companies are embroiled in a fierce competition. The contest: Who can build the most powerful offshore wind turbine?
From General Electric Co. to Siemens to MHI Vestas Offshore Wind, industrial giants are racing to build skyscraper-size turbines that can generate 10 megawatts apiece or more, a symbolic threshold for the wind industry. The more powerful the turbine, the cheaper it can generate electricity from a single location, generally speaking.
The prize in this engineering derby could be dominance over a multibillion-dollar offshore wind market that is set to boom in coming decades—notably in the U.S., where the Atlantic coast beckons as an ideal location for large-scale wind generation.
“There’s a kind of arms race under way,” says Aaron Barr, a principal consultant with research firm Wood Mackenzie Power & Renewables.
Bigger and Bigger
Offshore wind turbines have been growing larger for years as companies develop bigger and bolder designs. That’s helped steadily lower the price of generating power from wind.
When the first offshore wind farm, Vindeby, was commissioned in shallow waters off Denmark in 1991, its 450-kilowatt turbines stood 52.5 meters tall and had blades 16 meters long (or about 170 feet tall and 52 feet long). The turbines were designed by a company that’s now part of Siemens Gamesa Renewable Energy , in which Siemens has a majority stake.
Vindeby’s 11 turbines, decommissioned last year, would be lilliputians compared with the mammoth machines now being built. According to the Global Wind Energy Council, the average offshore turbine installed in 2017 was a 5.9-megawatt (or 5,900 kilowatt) machine. GE’s model of around that size, 6 megawatts, is 170 meters tall.
The most powerful turbine currently in existence, MHI Vestas’s V164 prototype, is capable of generating 9.5-megawatts of electricity, and is 187 meters tall, or roughly twice the height of the Statue of Liberty. Its 80-meter-long blades stretch nearly 12 meters farther than the wingspan of a Boeing 747.
“We are simply trying to push it to the limit all the time to see how far we can go,” says Torben Larsen, chief technology officer at MHI Vestas, a partnership of Vestas Wind Systems A/S and Mitsubishi Heavy Industries Ltd.
Offshore wind-power capacity has multiplied in the last decade, increasing to 18.7 gigawatts in 2017 up from 1.1 gigawatts in 2007, according to data from the International Renewable Energy Agency. A gigawatt, which is equal to 1,000 megawatts, is roughly as much power a small nuclear power plant is capable of generating.
The Race to 10
The next phase in the competition is surpassing the 10-megawatt barrier.
An executive at Siemens Gamesa Renewable Energy teased the idea of such a large machine in 2016, but the company has been largely mum on its efforts since.
“Expect an announcement to come,” says Markus Tacke, chief executive of Siemens Gamesa.
German turbine maker Senvion SA caused a stir in the industry last year when it revealed it was working on a “10-plus.” It expects to have a prototype in 2020 and to be ready to start installing them in wind farms by 2022.
But it was GE that made the biggest splash when it announced plans for a 12-megawatt turbine in March. Known as the Haliade-X, it would stand nearly three times as tall as the Statue of Liberty and harness wind with blades that sweep an area the size of seven football fields. If it were to be installed on a typical German North Sea site, GE estimates the machine could generate enough power to supply 16,000 European households.
Some in the industry have greeted GE’s plans with skepticism, noting that its biggest current turbines are just 6 megawatts, far short of the big boys. Jérôme Pécresse, chief executive of GE Renewable Energy, says the questions GE pondered before moving forward included, “Can we do this kind of blade? Can we find installation vessels that are going to install the turbine?”
Indeed, the companies building ever-larger turbines all acknowledge that building a more powerful turbine is more difficult than just making the tower taller or the blades longer.
How do you safely and quickly move turbine blades the length of soccer fields? Will cranes and ships need to be redesigned to handle bigger turbine towers? How soon can new factories and other infrastructure be built in emerging markets?
Rahul Yarala, executive director of the Wind Technology Testing Center, a massive, hangar-like facility in Boston where wind blades are put through their paces, says one big question is whether blades can be built in segments instead of as a single piece.
That, he says, would make them easier to transport, but engineers would need to ensure that the assembled blades were sturdy enough to handle the stress of turning in potent winds.
Companies are also working to make the turbines as smart, and digitally adjustable, as possible, so that workers can remotely change the pitch of a blade to catch more wind, or diagnose and fix problems without having to make costly, time-consuming trips offshore.
“The heart of any system is the control system,” says Danielle Merfeld, chief technology officer at GE Renewable Energy. “If you build those algorithms right you have essentially increased the IQ of your turbines.”