> so why is their service life so much shorter than some planes have had? The lifespan is typically 20 years unless there is a catastrophic failure (huricane,

> so why is their service life so much shorter than some planes have had? The lifespan is typically 20 years unless there is a catastrophic failure (huricane, typhoon, manufacturing error, etc). There are some major differences in how turbine blades and airplane wings behave: - A wind turbine blade suffers gravitational, centrifugal and aerodynamic loads about 10 times per minute, 2500h - 3000h/year. These forces can be up to 20kN[0]. (vs. plane only accelerates for take-off and landing very few times a day, and is otherwise is a relatively steady load regime) - Blades are now much bigger (http://images.gizmag.com/gallery_lrg/siemens-75m-tubine-blade-4.jpg http://images.gizmag.com/gallery_lrg/siemens-75m-tubine-blad...) and weigh between 6 - 30 tons. - Wind turbines are often in remote locations, and maintenance can't happen every time they come to an airport (predictive diagnostics by embedding sensors in the blades is starting to change this) Generally, fibre reinforced polymers are great materials for the job and there are a variety of applications for the recycled fibres (filling for new blades, downcycling, architecture, etc [1]) [0] https://www.sintef.no/globalassets/project/deepwind-2012/deepwind-presentations-2012/a1/cox-k.pdf https://www.sintef.no/globalassets/project/deepwind-2012/dee... [1] http://www.sciencedirect.com/science/article/pii/S0301421512002819 http://www.sciencedirect.com/science/article/pii/S0301421512...