What Happens to Wind Turbine Blades After They Die? | Dr. Paul Leahy | TEDxKlagenfurt

Key Concepts:

• Wind turbine blade decommissioning
• Composite materials (plastic resin and woven glass fibers)
• Waste hierarchy (reduce, reuse, recycle, recover, dispose)
• Repurposing vs. Downcycling (shredding/grinding)
• Technical, environmental, social, and economic feasibility
• Life Cycle Analysis (LCA)
• Building regulations and reform
• Blade repurposing superstore

1. The Problem of Wind Turbine Blade Waste:

• Wind turbine blades are made of composite materials (plastic resin and woven glass fibers) that are difficult to separate and recycle.
• The current standard solution is landfilling, which is unsustainable due to the large volume of blades being decommissioned. An image shows approximately 200 blades occupying 2,000 square meters of landfill space.
• Downcycling methods like shredding and grinding are energy-intensive and result in low-value filler materials. The world is already full of fillers derived from different types of waste materials.

2. The Rewind Initiative and Repurposing Solutions:

• Researchers from Ireland, Northern Ireland, and the USA formed a community called Rewind to find repurposing solutions for end-of-life wind turbine blades.
• Rewind aimed to find solutions near the top of the waste hierarchy, focusing on technical, social, environmental, and economic feasibility.
• The team brainstormed about 50 different ideas and assembled them into a blade repurposing atlas.

3. Technical Feasibility and the Blade Bridge:

• Repurposing blades is challenging due to their curved, tapered, and complex geometry. No two blades are exactly the same.
• The team 3D scanned blades to map their external geometry and used cutting, drilling, and burning to analyze their internal structure.
• They built a bridge using repurposed wind turbine blades as the main load-bearing elements.
• The bridge was tested to destruction with 33 tons of concrete blocks, but it did not break, demonstrating the strength and durability of repurposed blades.
• The blade bridge, located on a greenway near Cork, Ireland, has a lower environmental impact and carbon footprint than a conventional bridge because the blades replace concrete and steel.
• The blades used in the bridge had previously been used on wind turbines in Denmark and Ireland, highlighting their extended lifespan.

4. Environmental and Social Feasibility:

• Life cycle analyses (LCAs) showed that repurposing blades is environmentally superior to landfilling or incineration.
• Research with local community groups indicated strong support for using repurposed blades in structures.

5. The Future of Blade Repurposing:

• Future blades will be larger and stronger, requiring manufacturers to design them with repurposing and recycling in mind.
• Manufacturers should release design details to facilitate future repurposing efforts.
• In the next 5 to 10 years, 40-meter blades will become widely available, enabling the construction of larger structures like 25-meter span bridges and 30-meter telecommunications masts.
• Larger blades, such as the 125-meter blades from Mingyang in China, could be used in stadiums, highway bridges, and coastal protection barriers.

6. The Blade Repurposing Superstore and Building Regulation Reform:

• The speaker envisions a "blade repurposing superstore" where designers can browse and select blades based on their specifications, size, location, and availability.
• Radical reform in building codes and regulations is needed to allow the use of repurposed materials in new structures.
• The construction industry contributes significantly to global greenhouse gas emissions, with a third of those emissions coming from raw materials processing.

7. Three Deep Shifts for the Future:

• Shift 1: Change the perception of wind turbine blades at the end of life from waste to resource.
• Shift 2: Reform building regulations to allow the use of repurposed materials in new structures.
• Shift 3: Create a blade repurposing superstore to facilitate the selection and use of repurposed blades.

8. Notable Quotes:

• "A composite is a magical mixture of two different substances."
• "Testing to failure or testing to destruction is a nice phrase that we like to use for breaking stuff."
• "Repurposing is going to continue to test our ingenuity. But in a world that's faced with a climate crisis and finite resources repurposing is the only choice we have as the creators the inventors and the designers of the future."

9. Technical Terms:

• Composite Material: A material made from two or more constituent materials with significantly different physical or chemical properties that, when combined, produce a material with characteristics different from the individual components. In this case, plastic resin and woven glass fibers.
• Life Cycle Analysis (LCA): A method to assess the environmental impacts of a product, process, or service throughout its entire life cycle (from raw material extraction to end-of-life disposal).
• Downcycling: Recycling a material in such a way that the resulting product is of lower quality or has less functionality than the original.
• Repurposing: Using something for a purpose other than its original intended use.

10. Synthesis/Conclusion:

The video highlights the urgent need for sustainable solutions to manage the growing volume of decommissioned wind turbine blades. Landfilling is not a viable long-term option. The Rewind initiative demonstrates the technical, environmental, and social feasibility of repurposing blades for structural applications, exemplified by the blade bridge in Ireland. The speaker advocates for a shift in mindset, regulatory reform, and the creation of a blade repurposing superstore to facilitate the widespread adoption of repurposing practices. Ultimately, repurposing is presented as a necessary choice in a world facing climate change and resource scarcity.