Wind energy is increasing in popularity worldwide as a low-cost, carbon-free energy technology. In addition, With the rapid growth in the number of wind farms around the world, the recycling of wind turbines and waste generated from wind turbine blades has become a challenge. Figure 1 shows over 50 million metric tons of waste by 2050 from blades [1].
The purpose of this article is to expand on current knowledge about the recycling of wind turbines.
Recycling wind turbines plays a prominent role in increasing the number of wind farms. Up to 95% of materials used in wind turbines are made out of recyclable materials that would otherwise go to landfill if they are not recycled, and by recycling them we not only decrease CO2 emissions but also reduce the waste introduce to the environment [2].
What is the lifespan of a wind turbine?
The lifespan of wind turbines is about 20 to 30 years.
When wind turbines eventually reach the end of their lifespan,
the decommissioned turbines should be recycled.
[2]. Wind turbines have been built to save nature so they should be recyclable, but how?
What are wind turbines made of?
Wind turbines are made of fiberglass.
Fiberglass is a key part of the composite—a material made up of multiple constituents such as polymers and fibers—used to create wind turbine blades [3].
How wind turbines are recycled?
Tower:
The wind turbine tower can be torn down into several pieces or be made to fall with a targeted detonation. The foundation is then carved out of the ground, whereas pile foundations are left in place since removing them would cause unnecessary damage to the soil structure. Removed concrete is used for road construction, but reuse in other applications is often still difficult due to the concrete’s diminishing quality. Provisions must be made to ensure the fiber-enforced plastic particles from the tower are not blown into the environment. [6].
Blades
Modern utility-scale wind turbines have three hollow blades, made from composite materials including carbon fiber, fiberglass, binding agents, and reinforcement materials. The figure below shows the structure of a wind turbine blade (Figure 2) [4].
“Diagram of blade structure”
In order to recycle wind turbines, there are four main categories of options for blades at the end of their intended life: disposal, whole blade repurposing, partial blade repurposing, and reuse of material after reformatting [4].
Fiberglass recycling :
The technology used often is Recycling pyrolysis—a process in which organic components of a composite (e.g., resins or polymers) are broken down by intense heat in the absence of oxygen and are separated from the inorganic fiberglass reinforcement. The process converts organic products back into raw hydrocarbon products called syngas and pyrolysis oil, which can be used for energy production. This gives the process a net positive energy output.
The separated recycled fiberglass then can be cleaned and collected for direct reuse in the manufacturing of new products [3].
Possible methods for waste disposal, energy, and material reuse, notably wind turbine recycling to reclaim individual fibers in CFRP and GFRP (Figure 2) [5].
Figure 3
REFERENCES
[1] engineering-wkshp2022-8-3-murray.pdf
[2] https://oceanwindone.com/resources-and-faqs/seven-facts-about-offshore-wind/recycling
[3] https://www.energy.gov/eere/wind/articles/carbon-rivers makes-wind-turbine-blade-recycling-and-upcycling-reality support
[4] https://aiche.onlinelibrary.wiley.com/doi/full/10.1002/ep.13932
[5] https://journals.sagepub.com/doi/10.1177/0734242X221135527
[6] https://www.cleanenergywire.org/factsheets/resources-and-recycling-needs-germanys-wind-turbines#:~:text=The%20tower%20can,into%20the%20environment.
