Welcome to Sm.
Just out of curiosity, you said your machine is driven by wind, correct?
Are you are trying to achieve a basic windmill-type of animation or?
I ask because after doing some quick research on Piezo Electronics, it looks like it works more on vibration or impact rather than a brushless-motor-type of generator?
Do you have a picture you could show us of your model, and what you would like it to do, as I really don't think a full-on dynamic simulation is needed here if all you wish to do is to see it moving
...plus, it will render much faster without all of the calulatory overhead
Israel "Izzy" Long
Motion and Title Design for Broadcast-Film-DS