Will disposable wing become windmills again? Technically it is possible, now practical

A little windmill wiek in your car, surfboard or camping table. Windmolenbladen were known for a long time as impossible recyclable, but in the now there are countless possibilities in theory.

Although the developers of wind farms are struggling (expensive materials, high interest rates, and low electricity prices), there is no doubt about one thing: a lot of waste is released in the sector. This year alone, 60,000 tons of composite waste comes from turbines that are dismantled, according to TNO, which is based on data from Windeurope. For example, because they are being replaced by new copies. That would rise to more than 800,000 tons in 2050.

TNO is working on a smart solution that, the research institution hopes, can also be commercially interesting. In Petten in North Holland there is a glowing hot oven in which shreds of windmolenwiek are heated. Part of the Wiek acts as fuel for the process, and so the costs of the recycling could be reduced. « A very nice project, » says research leader Harald van der Mijle Meijer.

The newest blades are now longer than a football field

A windmill consists largely of steel. That is easy to recycle and is mixed with new steel. But De Wiek is a completely different story. It must be light and at the same time have a lot of tension – the newest blades are now longer than a football field.

To obtain that power, wicks are for the most part made of fiber composite (a combination of fiber optic or carbon fiber). That is mixed with plastic resin to keep things together.

Recycling that ultra -hard mixture is a difficult story. In Europe, therefore, windmill wings often end up on the landfill, but legislation will soon be prohibited. Or they will – as usually in the Netherlands – go to the waste incineration system via the shredder.

In 2020 a photo appeared from the United States: hundreds of discarded blades were buried under the ground out of misery. More creative is building a playground of Oude Wieken, as happened in Rotterdam, or making furniture. But for tens of thousands of tons of waste, that is not a solution.

The best option we now have in practice is ‘low -quality’ recycling in the construction sector. Wicks are ground and processed in a building material, says Van der Mele Meijer. « But we shouldn’t want that, because they are plastics. So when placing in water or soil, microplastics can be released. »

Burn fiberglass cleaning

Fortunately, researchers around the world are working on an alternative, including in Petten. Van der Mijle Meijer tells how he puts fragmented blades in the special oven with his team, and heats up to 500 degrees without oxygen. The plastic resin is converted into gas, and the fiber optic remains behind. After that, oxygen is added, so that the liberated fiber optic is burned. For this step, the gas from the resin can be used as fuel, which saves energy and therefore makes it financially more attractive.

This would be a good option for the planet. According to an estimate that TNO made if you were to dismantle the Windparken Borselle I and II in this way, that more than 50 kiloton Co₂ Save (compared to combustion).

Winning new material is cheaper than collecting, sorting, cleaning and recycling ‘old’ material

Renewi, one of the largest recyclers in the Netherlands, has also been hooked up. Because although the recycling sector is in heavy weatherwaste processors remain in search of the « waste streams of the future, » says Piter Brandenburg of Renewi. « The huge wind farms that have been built must be replaced in their entirety or partially at some point. »

But one question is important for commercial waste processors: is it possible? With recycling (also think of plastic or textile recycling), the problem is often not in technology in itself. The problem is the lack of a business case. Winning new material is cheaper than collecting, sorting, cleaning and recycling ‘old’ material.

« Glass fibers from the blades have to compete with new fiber optics, the price of which is actually very low on the market, » says Van der Mele Meijer. « So the process must be as cheap as possible. » In addition, it could help to use the resin as fuel.

And not only can the process cheaper, getting the glass fibers clean is also important, says Brandenburg. Recycled fiber optic can go to all kinds of things, think of autobumpers. « But if it is so clean that the weather is similar to new glass, then it has a higher value. Then you can really turn it into a nice new product. For example: new windmill wings. »

Second -hand mills

In fact, it is even better not to throw away Dutch windmills quickly. They are often dismantled after twenty years old, while they are still in good condition. The Netherlands Environmental Assessment Agency pointed out that wind turbines are often replaced by more energy-efficient, larger ones before the end of their technical lifespan. That is why there is also a second -hand market for old Dutch wind turbines. Our old windmills go to the United Kingdom, Italy, Sweden, Poland, or even Kazakhstan.

But precisely because windmills are getting bigger and bigger, the logistics of this second -hand market is becoming increasingly difficult. The newest generation of wind turbines is up to a factor six times higher than the first, Thus the Central Bureau of Statistics. For example, new turbines have a tip height of 247 meters. Just transport that. This way recycling becomes an interesting option again.

Shipping hulls and carashboards

Moreover, it is not just about windmills. The recovered fiber optic can be used again for ship hulls, paddles, surfboards and carashboards, says Van der Meijer says « you can actually find it everywhere, » says Brandenburg. « Up to and including the wall panels in NS trains. Volume is important for a waste processor. » In fact, this recycling market cannot live on the wind, says Van der Mele Meijer. « This can be an interesting technique for all markets in which composite materials are used: construction, transport, electronics, furniture, so on. »

And yet, even with a lot of volume, the recycling market often needs a boost. Think of recycling packaging plastic: there is more than enough, but one recycling company goes bankrupt after the other. It is not without reason that Renewi put his signature under a letter of fire last week About the ‘standstill’ of the circular economy in the Netherlands (in addition to companies such as IKEA, BOL and AUPING). Whether subsidies or obligations for the use of recycled material, they find: there must be more control from the government, it really works with the circular economy.

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