Cambridge scientist helps China make wind turbines from bamboo
A Cambridge scientist is helping China make the most out of two of its most abundant natural resources by developing wind turbine blades out of bamboo.
Dr Jim Platts, lecturer in the production processes group at Cambridge University’s Institute for Manufacturing, has been working with a number of Chinese partners to prove that bamboo can be used as an alternative to energy-intensive fibres and polymers for the demanding hi tech application.
China currently has a wind energy capacity comparable to the whole of Europe.
The majority of wind turbine manufacturers use glass and carbon fibres in polymer matrices as the primary structural material for blades.
Dr Platts, who has spent over twenty years developing the design and manufacture of blades for wind turbines, said that since bamboo is also a sustainable resource this makes wind energy a very attractive proposition for sustainable electricity generation.
“China is poised to move swiftly to develop its own wind turbine industry to exploit its wind energy capacity which is as large as Europe’s.
“China could so easily have followed the trend of the vast majority of wind turbine manufacturers in the world and used glass and carbon fibres in polymer matrices as the primary structural material for blades.”
All the blades which power the world’s growing number of wind turbines are made of composite materials.
However, from the beginning, the best blades have used wood – a naturally growing fibre reinforced composite material – as the primary structural material, comprising some 70 per cent of the weight of the blade.
This has been done because wood has superb fatigue behaviour and an unbeatable strength-to-cost ratio and it is also a low energy input material.
Over 20 years the wood used has progressed from khaya (African mahogany) to poplar to Finnish birch, birch being the best wood available for this usage in the western world.
The only wood available which has better properties than birch is bamboo, according to Dr Platts, and a supply route is now being developed for this material.
He said: “A few years ago, Chinese material resources were rarely considered in relation to technical matters such as this. But bamboo outranks birch as the natural material with the highest properties available, for this kind of application. And if notional values are given to good quality bamboo, the figures show that it outclasses even Finnish birch.”
Dr Platts is establishing the company, Composite Technology (now part of Vestas), as a major contributor in the wind industry, producing high performance blades for wind turbines up to 120 metres diameter.