Of Wind Turbines and Gummy Bears
Although wind itself is a renewable energy source, turbine blades used for harvesting wind energy create a huge waste when they reach the end of their lifespan. To prevent this waste build-up, scientists have developed a new material. Thus, when the gigantic turbine blades, some reaching 70 meters in height, could be recycled into kitchen counters, spare car parts, diapers, or even safely consumable gummy bear candies.
Wind turbine blades are generally made of fiberglass. While some companies have managed to transform obsolete blades into lower-quality recycled products, these eventually often end up in landfills. Moreover, blades become larger every day, as bigger blades mean more efficient energy production. Therefore, even fully functional blades can sometimes be dismantled and replaced with larger ones.
John Dorgan, a Michigan State University researcher, obtained a thermoplastic resin strong enough to be used in turbine blades or automobile parts, by mixing fiberglass with one plant-derived and one synthetic polymer. More interestingly, when this resin is digested in an alkaline solution, the reaction yields a material called PMMA (polymethyl methacrylate) that is widely used in homes and automobiles. When PMMA is heated, it turns into methacrylic acid, a super absorbent used in diapers. One by-product of this process is potassium lactate, which can be purified and made into sweets. “We recovered food-grade potassium lactate and used it to make gummy bear candies, which I ate,” says Dorgan.
This new material has the potential usage for not only manufacturing wind turbines, but also many other products, from kitchen countertops to laptop cases.
According to Dorgan, “The beauty of our resin system is that at the end of its use cycle, we can dissolve it, and that releases it from whatever matrix it’s in so that it can be used over and over again in an infinite loop. That’s the goal of the circular economy.”
REFERENCES
- 1. https://phys.org/news/2022-08-turbine-blades-recycled-sweet.html
- 2. https://www.theguardian.com/environment/2022/aug/23/wind-turbine-blades-could-recycled-gummy-bears-scientists