With blade diameter measuring more than two football fields, GE Renewables’ Haliade-X turbines are already the largest and most powerful in the world, capable of generating as much as 14 MW of energy. The ability to 3D print the turbine’s concrete base on-site, for direct transportation into the final at-sea location, will enable even larger systems to be built and deployed.
This approach is expected to enable the production of much taller wind turbines because turbine producers will not be hindered by transport limitations—today, the width of the base cannot exceed 4.5 meters for transportation reasons, which limits the height of the turbine. By increasing the height, the generation of power per turbine can also be increased substantially: for instance, a 5 MW turbine measuring 80 meters generates about 15.1 GWh a year. The same turbine measuring 160 meters would generate 20.2 GWh per year, an increase of 33%. How that scale is expected to become even greater, with new turbines reaching heights of 260 meters and even more.
The first prototype of the Heliade X turbine became operational in Rotterdam Port, in the Netherlands, just over a year ago. It became the first wind turbine to produce 288 megawatt-hours of energy within 24 hours. That may have been enough to power 30,000 households in that area.
The new offshore Haliade-X turbine features a 14 MW, 13 MW or 12 MW capacity, 220-meter rotor, a 107-meter blade, and digital capabilities. It is not only the most powerful wind turbine in the world but also features a 60-64% capacity factor above industry standard. The capacity factor compares how much energy was generated against the maximum that could have been produced at the continuous full-power operation during a specific period of time. Each incremental point in capacity factor represents around $7 million in revenue for the turbine’s owner over the life of a windfarm.
In October the machine, which is also the most powerful offshore wind turbine operating today, produced 312 megawatt-hours of energy in a single 24-hour period. Engineers from GE Renewable Energy have spent the last year collecting data on the Rotterdam prototype in order to obtain a full “type certificate” for the machine — verification from an independent body, DNV GL, that the new turbine will operate safely, reliably and according to design specifications. DNV GL awarded that certification to the offshore Haliade-X 12 MW.
“This is a key milestone for us as it gives our customers the ability to obtain financing when purchasing the Haliade-X,” said Vincent Schellings, who leads the development of the turbine for GE Renewable Energy. “Our continued goal is to provide them the technology they need to drive the global growth of offshore wind as it becomes an ever more affordable and reliable source of renewable energy.” It’s a good business to be in: The International Energy Agency has projected cumulative investment in offshore wind to hit $1 trillion by 2040.
The type certification came shortly after a constituent part of the turbine — its 107-meter-long blade, which exceeds the length of a football field — received its own component certification. The process of certifying the Haliade-X 12 MW involved separate testing of its blades, at facilities in the U.S. and U.K., and tests involving the prototype in Rotterdam.
GE designed the Haliade-X to generate 12 megawatts, but testing in Rotterdam revealed that it could outperform its original goals, to the tune of 13 megawatts. The new type certification specifically involves the 12 MW; testing of the Rotterdam prototype at 13 MW power output is underway now, with separate certification expected in the first half of 2021.
Next up after that milestone? Installation. GE Renewable Energy signed the first contract for the Haliade-X 13 MW, agreeing to supply 190 of the machines to Dogger Bank A and Dogger Bank B, the first two phases of what is expected to be the world’s largest offshore wind farm, located in the North Sea, some 130 kilometers off England’s Yorkshire coast. Scheduled for completion in 2026, the farm is projected to be capable of generating 3.6 gigawatts of electrical power — enough to supply 4.5 million U.K. households.
The challenges associated with producing larger wind turbines don’t stop at the base. The 100+ meter long blades also have to be produced as a single part—they cannot be assembled from multiple sections—and the strength of fiberglass reinforced plastics is reaching its physical limits in standing up to increasingly large wind forces.
Today the blades are produced using extremely costly, advanced molds which are not just extremely large but also need to be very complex to enable effective cooling and curing of the fiberglass reinforced blade. In the future, large-format composite 3D printing technologies may enable more cost-effective production of these blade molds and—perhaps even direct production 100+ meter long carbon fiber reinforced blades. Clearly, these capabilities are not available today, but companies like Ingersoll and Themrwood have demonstrated that there is no inherent limit to the size of the large format composite 3D printing systems.
Back in 2018, the U.S. Department of Energy’s Wind Energy Technologies Office and Advanced Manufacturing Office had partnered with another large-format composite 3D printing company, Cincinnati Inc, to apply additive manufacturing to the production of large wind turbine blade molds.
3D printing was seen as a very attractive option for large products such as wind turbine blades, which are very labor intensive, primarily done by hand labor of depositing large amounts of composite material, making the molds themselves quite costly and timely to make.
In the wind-power industry, the use of additive manufacturing to directly produce custom blades from CAD could also mean optimized wind-turbine blades per tower in a wind farm. This means that the blades of each turbine could one day be optimized for the individual location, wind, and turbulence patterns at each and every location in the farm and in each different farm. Additive manufacturing is the technology that makes all this possible at a lower price-point and with shorter lead times.
This will not happen anytime soon so don’t hold your breath. AM still presents significant limits in terms of final material density and quality, process repeatability and costs. Not to mention that the technologies to produce objects this large as a single component have not been developed yet. However, if turbines will become larger and larger (and they will), their production processes will necessarily have to include 3D printing.
