Interview partner:  Siemens Gamesa / David Romero Vindel, Sustainability Senior Specialist

Reducing non-recyclable waste: pivotal role of circular design to advance to circular models

1. Could you please tell our readers what Siemens Gamesa is doing on the topic of circular economy?

For Siemens Gamesa, circularity is about:

• Ensuring a long life of products, designed to last 20 to 30 years. Many of these are still in operation and technically well-performing. That way, we can ensure we get the most benefit out of the material put into the product.
• Being operational and repairable. We aim to keep the turbines operating, using remote diagnostics and efficient service schedules. Furthermore, we ensure to repair and maintain the turbines on behalf of customers; - using spare parts not fully exploit the blades’ functional value to a larger degree.

In fact, a failed component not only calls for a repair. It is often also a golden opportunity to improve the component’s quality, thereby enhancing its effectiveness and reliability. A component with significantly reduced failure rate allows to increase energy production – regardless of the age of the wind turbine or its brand. Furthermore, in order to reduce costs, save time and increase sustainability, we made sure to have refurbishments centre across the globe

• Recycling: we have been working on national and European projects with competitors but also cross-sectoral partners. The early projects were mostly focused on recycling technology improvement, whereas the latter ones, like the DecomBlades project, is based on establishing a complete value chain that includes recycling companies but also end-user of the recycled materials. Also, we have launched the RecyclableBlade initiative, which ensures that our blades can be recycled at the end of their service life – the first ones are already installed and producing energy.

2. What are the biggest challenges that the wind sector is facing working in reducing non-recyclable waste?

Currently, there is a general  consensus across  the industry that around 85% to 90% of the total weight of the turbine can be recycled through standard routes. The most challenging parts to recycle are  the blades, because of the inherent properties of the composite materials used to build them.

Composite materials, as the name suggests, are two or more materials blended into one. The wind energy industry uses resins, core materials and fibres (glass or carbon). Once the resin is cured, we obtain a single material with outstanding properties in terms of weight and durability designed to last for decades and to resist extreme weather conditions.

For the above-mentioned reasons, recycling the blades of a wind turbine has been the main blind spot of the industry for many years. Until now, Siemens Gamesa has developed the first RecyclableBlade in the world, which uses low energy demanding processes ensuring the materials in the blades can be separated at their end of service life and used for new applications.

The RecyclableBlade is a simple but robust solution that leads the path to the final target of our sustainable agenda: developing 100% recyclable blades by 2030. The concept is Siemens Gamesa's response to a growing market need: how to design environmental-friendly turbines and improve their recyclability at the end of their life. The innovation relies on a change in the resin's formulation that makes it possible to efficiently separate it from the other components at the end of the blade’s working life. . To make it possible, the blade is immersed in a heated mild-acidic solution, which separate the resin from the glass fiber, plastic, wood, and metals. The separated materials can then be recovered from the solution and used in new products matching the technical properties of the materials, i.e. in the automotive industry or consumer goods.

3. Circular design could help in improving resources and material management, especially for end-of-life products. How would you see this potential for Africa?

The scarcity of raw materials is a challenge for industrial companies around the world, therefore integrating a real circular economy vision within internal strategies is mandatory for improving the use of resources and material management. Wind farms will have to be decommissioned in 10, 20 or 30 years and whatever we can re-use is increasing the value of the existing wind farms. At present, in the wind industry we see more and more repowering project of existing wind farms being developed. In fact, repowering involves dismantling existing turbines and replacing them with new generation wind turbines with higher efficiency.

In theory, there is potential in Africa like in any region.

4. Are there successful models in Europe that could also be implemented in African countries?

Although the wind industry is very young, we did not wait for the first wind farms coming to their end of life to solve the issue. As already explained, 85% to 90% of the total weight of the turbine can be recycled throughout standard routes. And for the remaining components, which are mainly the blades, Siemens Gamesa has a two-fold strategy:

1. We are contributing to recycling the new models of blades thanks to the Recyclable Blade technology. That is a commercial solution that some customers are already using in their offshore wind farms.
2. We are contributing to recycling the old blades that are currently installed. To achieve that, we have an active collaboration in national and international projects that aims to establish the basis for the future commercialization of sustainable technologies for recycling wind turbine blades.

But this is not a task for a single player. If we want to be successful and make wind energy even greener, we need the close collaboration of the complete value chain, including public administration. In this regard, public policies should actively support reusing, recycling, and the circular economy versus landfill. For instance, Europe has implemented a landfill ban for composite materials, and this is driving companies to accelerate their path to circularity.

Another European example: the wind industry’s recycling supply chains are slowly ramping up given the increasing number of re-powering projects, as for example is the case in Germany. Recycling supply chains are usually characterized by local small and medium enterprises.

Going forward, it could be an option to support the development of industrialized recycling supply chains that can offer comprehensive recycling solutions for all the key raw materials. For the recycling of offshore wind turbines, the development of recycling harbours could be an option where the recycling will directly take place.

And this is also valid in Africa, of course. In blade recycling businesses, logistics have an important role to play, and, because of that, the ideal scenario includes the development of local recyclers and local supply chains that help to reduce logistic costs, increase the sustainability of the region, and could drive those companies to add more value to their products or services.