Working together on circular reuse of wind farms

The demand for electricity will rise sharply in the coming years. Wind turbines are crucial to meet this growing demand in a sustainable way. Working towards fossil freedom does not only mean that the energy generated is fossil-free, but that the entire life cycle of a wind farm is as sustainable as possible. The importance of circularity will therefore become an important part of the entire project: when designing a wind farm, consideration must already be given to reuse afterwards.

In expert meetings during the Dutch Design Week in Eindhoven, a start was therefore made on answering the question: ‘What if... When dismantling wind farms, a gold mine of raw materials remains?’ Several experts shed light on this topic.

Thomas Hjort, Director of Innovation Offshore Wind at Vattenfall: "We have the technical expertise for the design of wind farms, but for innovative perspectives we are looking for the creative brainpower and input of sparring partners who are given all the freedom to come up with inspiring ideas that we would not have come up with."

“As an industry we are constantly pushing for sustainable solutions and the focus on circularity has now become even more important,” adds Gustav Frid, Environment & Sustainability Specialist at Vattenfall. We see sustainability challenges in the supply chains as well as a need to find and build out circular solutions at end of life. In this, Vattenfall want to be a positive force steering away from linear to circular solutions that bring value today but also to future generations.”

Circularity is more than recycling

According to Jacqueline Cramer, Professor of Sustainable Innovation at Utrecht University, many people think of circulair solutions mainly in terms of recycling, while it means much more: using fewer raw materials, for example, or avoiding having to use certain raw materials. Other examples include repairing a product or redesigning an existing product. As a last option, there is still energy recovery through combustion. Circular thinking therefore requires a process of awareness within society, business, and politics.

Jacqueline Kramer explains the ten different levels of circularity.

This requires not only a change in thinking, but also a change in action, because circularity is indeed more than recycling materials, says Nina Vielen-Kallio, Energy Transition Project Manager at consultancy firm ECHT. Eighty percent of our CO2 footprint comes from mining and the processing of all materials in general. When we reuse materials, it means that we achieve huge CO2 savings because we do not need new raw materials. If we are able to reuse materials and products even several times, we contribute even more to that CO2 saving.

Material transition

Professor René Kleijn of Leiden University sees the energy transition primarily as a material transition: we are switching from fossil fuels to the use of various types of metals such as lithium, rare earths, copper, cobalt, and nickel. Materials needed for wind turbines, solar panels, and batteries, among other things. At present, almost all the metals needed still come from China, but there is a need for resilient and responsible supply chains, in part from Europe itself. The war in Ukraine has shown how fragile our energy supply is. "For a renewable energy system, we will need to build an enormous standing stock of solar panels, wind turbines, and batteries in the next thirty years," says Kleijn.

In the meantime, Siemens Gamesa is also working circularity. For example, the company wants to use 'green' steel to reduce the CO2 footprint of the construction of the wind turbine towers by at least 63% compared to conventional steel, says Rob Kuilboer, Senior Technical Sales Manager at Siemens Gamesa Renewable Energy. The towers consist of about 80% steel. Green steel is made by using less energy-intensive production processes and by reusing steel waste. For the turbine blades that are at the end of their life, Siemens follows various routes, for example reuse for architectural purposes or reuse of the fibres and oil released when recycling. At Vattenfall's Hollandse Kust Zuid wind farm three turbines have the Siemens Gamesa Recyclable blade installed. Even if all blades can be recycled, this blade is designed to make the material recycling more efficient.

Hard numbers and creativity

Joep Breuer, Wind Energy Scientist at TNO, comes up with hard figures: in 2025 there will be 60,000 tonnes of waste from wind turbine blades, and that could rise to 800,000 tonnes in 2050. The good news is that the circularity of wind blades is now one of the requirements in the tender criteria of new wind farms, such as IJmuiden Ver. "We need to think about smarter products with less material and a longer lifespan, and about reusing materials. In addition, we must constantly think about whether there are other ways to convert the power of the wind into energy. And that requires creative minds!"

That creativity will come from the design studios Studio Carbon and Interactivist and architectural firms cepezed and Superuse (together with spin-off Blade–Made), among others. They are used to going off the beaten track, learning from nature, reusing materials, and working at the intersection of technology and systems thinking. Superuse/Blade–Made, for example, always works with a decision tree to provide insight into the hierarchy of material choices: first reducing material to reduce the environmental impact. Then they look at what can be reused, renewable or bio-based materials and materials made from recycled raw materials, before using conventional materials.

Moderator Froukje Jansen (l) in conversation with, from left to right, Jos de Krieger (Superuse/Blade–Made), Chris Kievid (Interactivist), Itika Gupta (Studio Carbon) and Ronald Schleurholts (cepezed)

Why, how, and what

Nik Grewy Jensen, Concept Director Sustainability in Off-Shore Wind at Vattenfall, summed up the why, the how and the what of the expert meetings. Why? There is only one planet earth, and its resources are not inexhaustible. How? By setting requirements and ambitions, we have clear goals to work towards. What should we do? Being innovative, looking for opportunities and making challenging decisions to promote circularity. The key words here are working together.

Photo wind turbine towers: Vattenfall/Markus Bäckström
Photo's expertmeeting: Vattenfall/about.today - Jeroen van der Wielen