Wind turbine blade end-of-life options: an eco-audit comparison
Wind energy has developed rapidly over the last two decades to become one of the most promising economical and green sources of renewable energy, responding to concerns about use of fossil fuels and increasing demand for energy. However, attention is now turning to what happens to end-of-life wind turbine waste, and there is scrutiny of its environmental impact. In this study, we focus on one aspect of this, the blades. We analyse and compare end-of-life options for wind turbine blade materials (mainly glass fibre reinforced plastic and carbon fibre reinforced plastic) in terms of environmental impact (focusing on energy consumption), using our own data together with results gathered from the literature. The environmental impacts of each end-of-life option are discussed, looking at processing energy consumption, the recycling benefits and the effect of blade technology development trends. There is considerable variability in the results, and lack of consensus on predictions for the future. We therefore analyse the results using a range of different scenarios to show how the ‘optimal’ solutions are influenced by trends in blade composition and end-of-life process development. The most environmentally favourable process is dependent on whether the materials used for the blades are glass fibre composite or carbon fibre composite. The extent to which process improvement might affect the viability of different end-of-life processes has been assessed by looking at ‘crossover’ points for when the environmental impact becomes favourable. This analysis gives new insight into areas where research into process technologies could be targeted to enable significant end-of-life environmental benefits.