Higher wind turbine towers not only create conditions for the utilization of higher wind speed and more stable wind conditions, but also can extend the wind power generation time and maximize the opportunity to capture wind energy. In addition, the demand for wind power above 100 meters is relatively high in the United States and Europe. For this reason, the concept of high-rise tower bridge is studied by using the technology of Siemens high tower bridge and Aihe University. The goal of the project is to create a new wind turbine tower design and manufacturing concept to capture wind energy at 120 to 140 m hub heights and reduce the cost per kilowatt hour of wind turbine towers built and operated in the United States. Siemens American Research Institute is responsible for the design, analysis and optimization of the wind turbine tower specially developed for this project.
Kurt bettenhausen, head of automation and control technology at Siemens US research institute, said, "for a long time, wind turbine manufacturers have been determined to build higher towers because at higher locations, wind energy resources are more stable and reliable. This project is likely to become a reality plan. "
Concrete replacing steel pipe
Today, most power station wind farms in the United States use stainless steel tube towers with a hub height of 80 meters. The tower is usually manufactured and transported in three sections, with a diameter of about 4.1 meters at the bottom, just below the interstate highway height limit. If the length of the currently popular tower is further extended by 20 or 60 meters, wind turbines will produce more power and can generate wind power in places where wind power is not yet economical. However, the modularization of steel pipes that require vertical joints is not only costly, but also requires strict quality control.
In view of this, Professor Sri sritharan of Iowa State University has worked with a Siemens US Research Institute team led by Suraj musuvathy to develop solutions to achieve higher wind turbine towers. "The key to a higher tower is to replace steel tubes with concrete," sritharan said Sritharan is developing towers that assemble precast modular concrete elements to achieve target heights.
The hexcrete tower is named after its hexagonal prestressed concrete columns and hexagonal tower sections. The whole tower is assembled from precast columns and slabs made of high performance / high strength concrete and / or ultra-high performance concrete.
Advantages of modularity
With the support of Siemens wind power and renewable energy group, Siemens US research institute is developing three-dimensional modeling, simulation and optimization algorithms to perform the design space exploration of modular concepts to determine design parameters that minimize the per kilowatt hour cost of building and operating wind turbine towers while meeting structural and design standards. In terms of tower construction and transportation, modularization is beneficial to increase flexibility.
Modular concrete components can be transported on trailers, without the expensive special trailers currently used to transport steel tube towers - hence the limitations associated with higher towers. With modular concrete elements, the tower base width can exceed 4.1 meters, which helps to build higher towers. The tower height can be increased not only by extending the base diameter, but also by increasing the size of its columns and plates, or a combination of the two. In addition, the concrete transportation costs can be reduced easily with steel pipes everywhere.
