Sky High

Photo: Iowa State University

In 2013, global wind power capacity reached 318,105 megawatts (MW). That’s enough energy to meet the electricity needs of more than 500 million people.

As the number of wind turbines across the world continues to increase each year, so does the need for units designed to maximize energy production. Steel towers – the current standard in the wind industry – are unable to reach heights greater than 330 ft, where steadier winds capable of higher energy output can be found. To combat this limitation, engineers are turning to the strength of precast concrete.

In Spain, Norten PH engineered a precast tower manufactured in segments and intended for on-site assembly. Thanks to a powerful self-consolidating concrete mix design, each turbine is capable of attaining heights of anywhere from 361 ft to 396 ft.

Similarly, Enercon, a wind turbine manufacturer based in Germany, recently began delivering a new line of units for a project in the Netherlands. By using precast concrete towers, the turbines reach an astonishing height of 440 ft.

Researchers are also studying increasing tower heights in the U.S. In September, the Department of Energy awarded engineers at Iowa State University a $1 million grant to investigate how high-strength precast concrete can be used to build taller, more productive towers. Sri Sritharan, a professor at Iowa State and leader of the College of Engineering’s Wind Energy Initiative, believes that the grant will help create new product line opportunities for U.S. precasters. Additionally, by relying on precast panels for the towers, Professor Sritharan feels transportation will be easier.

When other building materials reach their limits, precast concrete remains up for the challenge, allowing the wind industry to meet the increasing energy needs of an ever-expanding global population.