FLAG Project History #3

A project log for Flexible circuit wind generator

A new way to generate wind energy using only polyester film based flexible circuits

Stuart MacKenzieStuart MacKenzie 10/14/2021 at 06:040 Comments

It was May 2018 when I had the first successful test of a FLAG, oscillating in the wind to power a light.  Despite trying many different variations and circuits, you will notice the design still looks very similar to the original 4-sector 3-layer acrylic test shown in the last log.

In order to make the generator oscillate in the wind, I took a rectangular piece of polyester transparency, folded it in half, and cut out rectangular vent holes.  A second piece of polyester goes inside the "V", and when held in the wind, the center film oscillates at a fairly high frequency.  The center film covers one set of holes, causing the air to pass through the opposite holes, which essentially sucks the center film to the opposite site...  over and over, at high speed.  

The harvesting circuit and sectors stuck onto the film was made using ordinary aluminum foil tape, with the tips folded over wherever an electrical connection was needed.  Alligator clips were connected from the bottom two connections to power a fluorescent light.  The tabs of tape sticking out were what I used to hold it in the airflow from my "wind tunnel", and holding it relatively fixed like this makes the generator oscillate at much higher frequency.  This is something I still wish to experiment with further, as the latest FLAG designs run at a much lower frequency.  Generally speaking these sorts generators will theoretically make more power per unit volume at higher frequencies, with less travel, and more layers.

After all the effort in getting to this point, I had the first working FLAG framed. 

The generator still had some problems to be sorted out.  It still seemed to be sensitive to humidity, and the mechanical contacts were still unreliable.   More to come in the following logs.