Making wind turbine blades from waste

Hey folks,


I have been following PP for a long time but I never jumped in actively. I decided to change that today !


I would like to submit an idea a friend of mine had few years ago that we haven’t tried yet.

This friend and myself are involved in WindEmpowerment, which is a network of organizations and small companies around the globe working on small wind turbines and rural development.  This network is a knowledge platform that share a common design for self build machines a bit like PP but for rural electrification.  (If you want more infos


The idea we would like to submit is to reuse PET bottles and to up cycle them in wind turbine blades through a blowing process. (I’ve attached a schematic)

We thought that it would be super great if we could do a kind of a joint product together around this idea if you like it.

We do not have much experience with plastic (except some in extrusion and 3D printing) and we would love to have your feedback on the feasibility of re-blowing PET – and if you know some tricks or parameters (temperature cycle for instance) to master this technic.


We strongly believe that making a demonstrator would easily become viral on the internet and inspire many to start making energy from waste. The design would be fully open source and mould could be then sold on the bazar to allow people to replicate it all around the globe.


Looking forward to get your feedback/critics on the idea,




I was also thinking that in parallel of the experimentations with blowing technics it would be really interesting to test out making a regular mold for the injection machine. (as suggested @andyn)


Last possibility would be to extrude a regular airfoil and create plastic beams with the airfoil shape. This technic is maybe the simpliest from a manufacturing perspective, but offers quite poor aerodynamical results when used with an horizontal axis wind turbines.


suggested to go for a vertical axis wind turbine design to simplify the holding of the blade. Unforturnately we have really poor feedbacks on vertical axis wind turbines performances, and despite our many attempts at making many different designs, they never never produced much energy…





Oh, and I was wondering – tough question following –

Have you made some kind of datasheets one the mechanical properties of the recycled plastic ? I mean something like stress tests and shear tests for a given set of parameters like  | plastic type –  temperature – granulometry – | ?

I’ve quickly searched for it but haven’t found much on the forum.


It would be super useful for the design of mechanical products.