The earth is full of energy, but we need the right technology to access it. Initially, people mostly developed convenient, cheap but dirty methods (such as burning fossil fuels), but there is now a growing need to use cleaner and more evenly distributed methods such as solar power, waves, tides, nuclear power and of course , wind energy. energy.
Conflicts such as the war in Ukraine have also drawn attention to national energy dependency – now all countries are wary of relying on the energy of another country, especially if that country could become hostile. Some energy exporters have been making client countries dependent for political purposes for years, so many countries now want to become energy independent. Green technologies can make a big difference in this regard.
A more advanced energy alternative is wind power, and wind turbines are being built around the world (onshore and offshore). When it comes to efficiency, more is better for turbines, and modern designs are pushing the boundaries of materials, fasteners and fixtures, and transportation. Huge turbines require a lot of connections, especially since the blades are now made in segments due to manufacturing and shipping constraints.
There are about 36 manufacturers of large (10kW+) wind turbines worldwide, and according to the Guinness Book of World Records, the largest operating wind turbine is the General Electric Haliade-X, which is 260 meters (853 feet) tall and has a rotor diameter of 220 meters (721 feet). The first Haliade-X prototype was assembled for testing at the port of Rotterdam on October 17, 2019.
The Haliade-X rotor blades are 107 meters (351 ft) long and have a hub diameter of 6 meters (19 ft 8 in). The Haliade series is manufactured by GE Wind (Offshore), the European subsidiary of the American multinational company formerly known as Alstom Wind. Most of the production of the Haliade collection takes place in Saint-Nazaire and Cherbourg, France.
The original version of Haliade-X was rated at 12mW, but it was upgraded to 13mW after the first round of testing. In January 2020, the 13MW Haliade-X prototype set a new record for 24-hour power generation with a one-day output of 288MWh. The size of the turbine means that one revolution of the rotor generates enough electricity to power the average home for more than two days.
Haliade-X has also been selected for a major wind farm project by Dogger Bank, a group of wind farms under construction in the central North Sea. When completed, the wind farms will have 190 13MW Haliade turbines generating a total of 4.8GW.
GE Renewable Energy recently announced that it has added a second blade-making tool to Cherbourg. The company is also building an additional blade finishing facility. The plant also plans to hire 200 more workers, bringing the total workforce at the plant to 800. “Our Cherbourg team is delighted to play an active role in the energy transition and be part of the GE Haliade-X offshore wind turbine success journey,” said Olivier Fontan, President and CEO of LM Wind Power.
Usually workers make blades from layers of fiberglass and cork. The result is a composite material. They placed individual panels and beams in special molds that were sanded and polished to get the correct aerodynamic shape. They then covered the layers with foil, bled the air out to create a vacuum, and injected a special resin to fuse them together. The vacuum helps the resin seep into the smallest corners and create a strong shell.
The process seems simple, but workers in Tyvek white coats, respirators and goggles have to work quickly and fill huge molds with resin that quickly turns from liquid to solid.
When the blade skins harden, workers take them out of the mold and glue them together—the two halves of the skin that make up the blade—in a long, curved contraption. Finally, they grind, polish and varnish the blades before shipping to customers.
GE is also building another long blade plant at Teesside, a UK industrial port on the North Sea coast. Scheduled to open in 2023, workers at the plant will supply blades for the Haliade-X turbines at Dogger Bank’s offshore wind farm.
In October, GE also received an order for 62 Haliade-X turbines for the 800MW Vineyard Wind 1, the first offshore wind farm in the US. It will be built 15 miles off the coast of Martha’s Vineyard, Massachusetts.
MingYang Smart Energy also plans to launch a 16MW offshore wind turbine in 2024. The Chinese company said the world’s largest wind turbine under development could power 20,000 homes.
The rapid growth in demand for electricity from renewable energy sources and the declining cost of wind energy technologies have prompted Ming Yang to design the most powerful and largest wind turbines in the world. The model was named MySE 16.0-242, and the designers implemented the concept of a hybrid drive and opted for a compact solution. Offshore turbines are typically much larger than land based turbines.
MingYang claims that the 262-meter windmill will be able to withstand typhoons. The proposed main rotor has a diameter of 242 meters, blades of 118 meters and a swept area of ​​4.6 hectares. The tower and blades will be able to withstand the strongest winds, and the blades are curved so that they do not hit the tower.
One MySE 16.0-242 will be able to generate 80 GWh per year. In comparison, it produces 45% more power than Ming Yang’s previous turbine model, the MySE 11.0-203.
According to the announcement, the 16.0-242 can also reduce CO2 emissions by more than 1.6 million tonnes over an estimated 25-year lifespan. This is the start of Mingyang’s product portfolio for offshore installations of 15MW and above. Last year, China installed more than half of the turbines in this area worldwide.
So, how big can the towers and blades of wind turbines be? What additional requirements do they impose on fasteners and fixtures? In a US study, four energy research institutes interviewed about 163 experts, and based on their opinion, the average hub height of land-based turbines is expected to reach 115 meters by 2030, which is higher than the current hub height of about 33 meters. . The tip of the blade is over 170 meters from the hub.
By 2030, offshore wind turbines, which are already larger than land-based ones, will reach even greater heights, according to experts. Today’s machine with a hub height of 90 meters and an average power of 4.1 MW will be replaced by an 11-milliwatt machine with a hub height of 125 meters and a blade span of 190 meters. Their knives will cut through the air at twice the height of the Statue of Liberty.
“We asked experts to give us an idea of ​​typical turbine sizes in 2030, so the numbers should be considered averages, not maximum estimates,” said Ryan Wiser of Lawrence Berkeley National Laboratory, one of the institutions involved in the project. . Research work. According to the authors of the study, some of whom are from the US National Renewable Energy Laboratory, the University of Massachusetts and the International Energy Agency, this trend towards larger turbines is due to the desire for a lower levelized cost of energy (LCOE).
Larger turbines cost less per megawatt due to economies of scale and a smaller installation cost balance, and have better performance due to taller towers and longer blades. The size of onshore turbines in the US has increased 20 times, from 0.1 MW and 18 m in the 1980s to 2 MW and 82 m in 2015.
Offshore turbines have been developed in Europe for only fifteen years, but their average power has grown from 1.6 MW and 64 m in 2000 to 4.1 MW and 90 m last year. Due to a further increase in size, “relative to the 2014 baseline, the LCOE is projected to decline by 24-30% by 2030 and by 35-41% by 2050,” according to the study, which is considered the largest. The largest expert heuristic review of energy technologies ever.
As expected in a poll of diverse opinions, responses varied widely, with some experts predicting fixed-bottom offshore wind turbines could reach 18 MW by 2030.
“Typical turbine capacity onshore and offshore in Europe by 2030 is slightly larger than projected in North America,” Wither said. “European cars are expected to be larger than North American ones, which is in line with historical trends.”
Although the study did not take into account emerging markets, Aaron Daniels, co-founder and managing director of Thai consultancy Modern Energy Management, said large turbines are fast becoming the norm outside of Europe and the US. “The market is reacting,” he continued. “8MW wind turbines with 164m rotors are now commercially available in this segment, with some manufacturers planning to launch 10MW turbines.”
By 2030, even the upper limit of current size expectations may not be realistic, Weiser said. “Unfortunately, we did not ask about the maximum capacity or base limits,” he commented. “I would like to point out that in the past, most claims that we are reaching a plateau, at least so far, have turned out to be wrong.”
However, it is clear that wind turbines cannot grow indefinitely. Both Wither and Daniels have said that there may be an upper limit to the size of wind turbines that can be driven by logistics. “I suspect that at some point the recoil will start to decrease,” Daniels said. “It’s all about the cost of production and shipping.”
Another limitation may be the rigidity of the material. The large blades are already pre-bent so they don’t touch the tower in high winds. If the blade hits the turret at high rotation speed, it will deal massive damage.
When it comes to the wind turbine size, David Briggs, chief technical officer at the Cooper Turner Beck Group, explains the challenges regarding fasteners have also increased: “I started with Cooper & Turner 20 years ago when tower fasteners were M42s, and blade studs were M24s. When it comes to the wind turbine size, David Briggs, chief technical officer at the Cooper Turner Beck Group, explains the challenges regarding fasteners have also increased: “I started with Cooper & Turner 20 years ago when tower fasteners were M42s, and blade studs were M24s. Когда дело доходит до размера ветряной турбины, Дэвид Бриггс, главный технический директор Cooper Turner Beck Group, объясняет, что проблемы, связанные с крепежом, также возросли: «Я начал работать с Cooper & Turner 20 лет назад, когда крепления башни были M42, а шпильки для лопастей были М24. When it comes to wind turbine size, David Briggs, chief technical officer at Cooper Turner Beck Group, explains that issues with fasteners have also increased: ‘I started working with Cooper & Turner 20 years ago when the first fasteners were M42, and the studs for the blades were M24.谈到风力涡轮机的尺寸，Cooper Turner Beck Group 的首席技术官David Briggs 解释说，紧固件方面的挑战也在增加：“20 年前，我开始使用Cooper & Turner，当时塔架紧固件是M42，叶片螺柱是M24。 Regarding the size of the turbine, Cooper Turner Beck Group’s Chief Technology Officer David Briggs explained that the fastener challenge is also increasing: “20 years ago, we started using Cooper & Turner, and the tower fastener at that time was the M42 , 叶片读柱是M24。 Когда дело доходит до размеров ветряных турбин, Дэвид Бриггс, технический директор Cooper Turner Beck Group, объясняет, что проблемы с крепежом также возросли: «Я начал использовать Cooper & Turner 20 лет назад, когда крепления башни были M42, а шпилька лопасти — M24. When it comes to wind turbine sizes, David Briggs, technical director at Cooper Turner Beck Group, explains that fastener issues have also increased: ‘I started using Cooper & Turner 20 years ago when the main fasteners were M42 and the blade studs were M24. We are talking about fasteners with M82 heads and M48 blade studs, about a meter long. We also encountered a problem with the production of the M100. We had to find new materials that could be heat treated to get the right mechanical properties. It also presents health and safety issues. Working with this material at the M100 plant was a difficult task. About 70 kg each. ”
David continues: “In the wind turbine business, we ship from top to bottom. We supply bolts throughout the tower and fasteners in the nacelle and blade mounts. We also developed our own zinc flake coating which is very durable because it must withstand operational damage and harsh maritime conditions.
David also believes that the market for wind turbine adhesives and fasteners will grow significantly in the coming decades as the world turns to wind power as the main green alternative to fossil fuels. “As sizes get huge, fasteners and fasteners will struggle in terms of strength, quality control and failure detection. However, for those companies that make the right product, the market opportunities are huge.”
Will joined Fastener + Fixing Magazine in 2007 and over the past 15 years has been exposed to every facet of the fastener industry – interviewing key industry figures and visiting leading companies and trade shows around the world.
Will manages content strategy across all platforms and is an advocate for the magazine’s renowned high editorial standards.