How Green is Green Power?
The hidden environmental impact of windfarms.
Do you know the secret to clean, green, renewable energy? Here’s a hint: it’s not wind energy. At least, not in its current form.
Professor Chris Rudd OBE — Deputy Vice Chancellor and Head of Campus, Singapore for James Cook University — points out that, over the last two decades, the public has believed wind energy to be one of the greenest renewable energy sources.
This has led to governments around the world encouraging the development of wind farms. In fact, the newly installed wind power capacity has rapidly grown from 7,600 MW in 1998 to over 51.3 GW in 20181.
(Figure shows the newly installed wind power by region)
Professor Rudd continues, outlining his thoughts in a newly published research2, “Amidst this growth, attention is turned to the environmental impact from end-of-life turbine blades, especially when end-of-life blades and associated structures end up in landfills. Wind energy would not be effectively ‘green’ if anthropogenic materials are not given attention in a responsible manner”.
Indeed, the truth is that turbine design lifespan typically falls around 20 years. This means that wind farms and their turbines will produce a significant amount of waste at their end of life after 20 years. This is in addition to the waste already generated during the manufacturing and blade repairs stages. Experts predict that this will become a critical global issue as early as 20283.
(Figure shows turbine blade material usage forecast)
In order to dive deeper into this pressing issue, Professor Rudd is collaborating with Associate Professor of Business at James Cook University in Singapore Adrian Kuah, as well as with researchers from University of Nottingham Ningbo China — Dr Kok Hoong Wong, Dr Nai Yeen Gavin Lai, Dr Xiaoling Liu, Ms Siqi Hao, and Ms Jianan Mao.
It turns out, existing blades from wind farms at the end of their life are typically made of composites due to their light weight and mechanical properties. However, such material is difficult to recycle in an economically viable manner.
“As turbines grow larger in diameter, more blades are now reinforced using carbon fibre-reinforced plastic (CFRP), which are very expensive and non-biodegradable,” shared Associate Professor Kuah. “These broken blades are now sitting on mountain tops, as these are large structures and costly to bring down.”
That said, high-quality carbon fibres can be reclaimed from CFRP via a process dubbed “thermal pyrolysis,” allowing recycled carbon fibres to be reused in new composites.
What’s more, the findings revealed that by controlling the temperature, gas flow rate and heating rate of the pyrolysis, carbon fibre can be recovered more efficiently, while at a lower cost and at high quality.
Overall, this process is a prime example of the circular economy at work. The idea of the circular economy is at the forefront of the SICC-JCU Circular Economy + Sustainability Competition, where contestants are urged to develop a clear video message that explores opinions on the circular economy in order to invoke positive change in society.
The competition is a project spearheaded by the Singapore-based Circular Economy and Sustainability (CES) flagship of the Centre for International Trade and Business in Asia at James Cook University, in collaboration with the peak business Chamber in Singapore – the Singapore International Chamber of Commerce.
The Grand Finale of the SICC-JCU Circular Economy + Sustainability Competition will be held on 25 Oct 2019, 3pm at James Cook University. The event will see the finalists present their entries to a panel of judges, and have the winning entries selected. Registration is currently open to the public at [email protected]
Find out more about the Centre for International Trade and Business in Asia here.
Find further information on our areas of research and research strength at James Cook University in Singapore here.
1 GWEC, 2019. Global Wind Report 2018. https://www.gwec.net/wp-content/uploads/2019/04/GWEC-Global-Wind-Report-2018.pdf
2 Hao, S., Kuah, A.T.H., Rudd, C.D., Wong, K.H., Lai, N.Y.G., Mao, J., and Liu, X., 2019. A circular economy approach to green energy: wind turbine, waste, and material recovery. Science of the Total Environment. (Article in Press)
3 Liu, P., Barlow, C. Y., 2017. Wind turbine blade waste in 2050. Waste Manag. 62, 229-240