Wind power is one of the major avenues towards decarbonisation, with the International Energy Agency (IEA) predicting global annual offshore wind installations to increase by up to 50 per cent to over 30 gigawatts (GW) in 2027, propelled by policy support in the European Union, the United States and China. But, with legacy wind turbines from the early 2000’s now due to be decommissioned over the next decade, concern is arising about the recyclability of turbine blades.
According to Vattenfall, although 90 per cent of a wind turbine is already recyclable and most components – such as the tower, gearbox components and generator – are easy to reuse and recycle, turbine blades are made of composite materials and are therefore more challenging to recycle.
Composite materials are composed of at least two materials, which combine to give properties superior to those of the individual constituents. The many component materials and different processes that can be used make composites extremely versatile and efficient, typical resulting in lighter, stronger, more durable solutions compared to traditional materials. Composites UK, a trade association for the UK composite materials industry, states that carbon-fibre reinforced composite can be five times stronger than 1020 grade steel while having only one fifth of the weight.
Most blades are made with fibreglass-reinforced polyester or epoxy, with some blades utilising carbon fibre or aramid as a reinforcement material. Mixing materials in this way, however, means that recycling turbine blades is a complex, and often cost-intensive, process.
Increasing recyclability and circularity of materials
By the year 2050, material from decommissioned wind turbine blades is expected to generate 40 million tonnes of waste worldwide. Currently the general answer to what to do with old turbine blades is to put them into landfill, which is certainly not sustainable for much longer as many countries in Europe look to ban landfill from 2025.
The other alternative is to co-process them into cement, which can reduce the CO2 emissions from cement clinkering. While even the IEA recognises the importance of clinker substitutes, the process of creating the cement and concrete is still very energy-intensive, with current estimates suggesting the industry accounted for 2.6 billion metric tonnes of CO2 emissions in 2021 alone – a figure that continues to rise.
Last year, Vattenfall partnered with Gjenkraft in Norway to recycle turbine blades from a wind farm in the Netherlands, turning them into skis, snowboards and construction materials for solar farms. They have now set a target to recycle all dismantled wind turbine blades by 2030, and 50 per cent of the blades by 2025.
“We were looking for partners for our wind blade recycling project, came into contact with Vattenfall and since then we have been in constant contact with Gustav Frid about the process of the work in our project,” commented Marcin Rusin, co-owner of Gjenkraft. “When the wind turbines at the Irene Vorrink wind farm were dismantles, we were one of the first to offer to recycle the wind blades.
“In the recycling process we can adjust the parameters to obtain the properties that our customers expect from our products, making skis, snowboards and other products that contain glass fibres and carbon fibres.”
Recycling on an industrial scale
More recently, Denmark-based company Continuum has announced plans to make all of their wind turbine blades fully recyclable, and stop landfilling and their emissions-intensive processing into cement, with six industrial-scale recycling factories across Europe. The initiative is backed by investment from Danish venture capital firm Climentum Capital and a grant from the UK’s Offshore Wind Growth Partnership.
The result is a fully sustainable, ultra-low carbon footprint solution for an industry challenge that otherwise leaves mountains of waste.
“We need solutions for the disposal of wind turbine blades in an environmentally friendly manner, we need it now, and we need it fast, and this is where Continuum comes in,” says Nicolas Derrien, chief executive officer of Continuum Group. “As a society we are rightly focused on renewable energy production, however the subject of what to do with wind turbine blades in the aftermath of that production has not been effectively addressed. We are changing that, offering a recycling solution for the blades and a construction product that will outperform most other existing construction materials and be infinitely recyclable, and with the lowest carbon footprint in its class.”
“We need wind energy operators and developers across Europe to take a step back and work with us to solve the bigger picture challenge,” added Martin Dronfield, chief commercial officer of Continuum Group, and managing director of Continuum Composite Transformation UK. “Continuum is offering them a service which will not just give their business complete and sustainable circularity to their operations, but help protect the planet in the process.”
Each Continuum factory in Europe is aiming to have the capacity to recycle a minimum of 36,000 tonnes of end-of-life turbine blades per year, and feed the high value, infinitely recyclable product back into the circular economy by 2025.
The first of their six factories, in Esbjerg, Denmark, is set to be operational by the end of 2024, with a second factory in the United Kingdom to follow on just behind it. After that, Continuum are looking to build another four in France, Germany, Spain, and Turkey by 2030.
As part of their pledge to promote green behaviour, Continuum have designed their factories to be powered by only 100 per cent green energy and to be zero carbon emitting environments; meaning no emissions to air, no waste fluids to ground, and no carbon fuel combustion.
While climate change conspiracy theorists and renewable energy sceptics are quick to point out images of turbine blade ‘graveyards’ as a ‘gotcha’ moment for wind energy advocates, the reality is that wind energy remains a highly effective way of decarbonising energy grids. With further improvements in terms of recyclability already under development, now is the time to increase the scalability of wind energy to new heights.