Wind turbine blade reuse for sustainable urban design: Denmark turned a retired wind turbine blade into a bicycle shelter in 2019; 7 years later, it remains a model for circular urban design

In 2019, the Port of Aalborg in Denmark found an unusual use for a discarded wind turbine blade. Instead of cutting it into smaller pieces for disposal or fuel, the port turned part of it into a shelter for bicycles. The idea came from a simple need; the port needed a new bicycle shed, and an online search gave Brian D. Rasmussen an unexpected solution.

Rasmussen works with construction and environmental matters at the port. While looking at bicycle shelter designs, he spotted one in New York that reminded him of a wind turbine blade. Since Siemens Gamesa operates a major blade factory next to the harbour, he had a way to explore the idea.

He contacted the company and obtained the middle section of a discarded blade. Its root end was needed for a test in Germany, but the remaining section was available for another use.

Denmark Turns Retired Wind Turbine Blade Into Bicycle Shelter

Wind turbine blades are built to handle strong winds and repeated loads. Their composite materials make them relatively light for their size, while providing the strength needed during turbine operation. Those qualities made the blade a promising candidate for a shelter, but its original design came with limitations.

A blade is engineered to attach at its root and rotate in changing weather. The port planned to rest it on two supports and cut away much of its underside. That changed how the structure would carry loads, creating safety questions.

A full blade can weigh more than 20 tons. Engineers design blades to bolt in at one end and spin in high winds. Laying a cut section flat on two supports changes the physical forces entirely. Cutting open the composite material also makes the structure bend and lose its shape.

There was another problem. The manufacturer did not provide the detailed drawings and construction data Rasmussen needed for the conversion. He made a small model from cardboard and wood at home, cutting into it to see how the shape and stability changed.The shelter addresses a problem the wind industry continues to face; what happens to blades when they are no longer needed? Their composite construction makes them difficult to recycle using conventional methods. Finding practical uses for retired blades is one way to keep some of that material in service.

The Aalborg project offers a different approach from breaking a blade down for processing. A section that already has a strong, curved form can sometimes be adapted for another job. In this case, the port turned an unwanted industrial component into something useful for everyday transport.