Seems like a fun project to replicate “…a windmill with a diameter of just 10cm which works by flexing piezoelectric crystals as it rotates, causing them to generate a current. A ‘gentle breeze’ of 16km/h is enough to generate the 7.5mW necessary to power a small electronic sensor. Such windmills are designed to solve the problem of powering Wi-Fi kit in remote locations. Geologists, for instance, can monitor seismic activity using wireless-enabled sensors located across large geographical areas.” [via] Link.
