Micro Wind Turbine Test

For my ECE 101 class we had to make an invention, although it didn’t have to be electrical. The first thing that came to mind was a small wind turbine. Basically, I wanted to make something that could be mounted on the window of a school bus or a greyhound bus so people could charge their electronic gadgets with ease from their seats (assuming they don’t have access to any other power source from the engine).

After running some calculations I found that this could be a pretty fun and challenging problem to work on. I would need to make a generator that would work at very high wind speeds (upwards of 80 mph) to ensure I had a little bit of a margin of safety. I figure a typical greyhound bus probably doesn’t do much over 85, figure in a bit of a headwind and it could probably experience a bit more than that.

Barley lighting an LED with the power from a fan. The turbine would light 4 in a 25 mph wind though.

After running some calculations for a 3 inch diameter rotor I found that my main problem would be making the whole system inefficient enough to not over charge common electronics and blow the stator all together. Originally, I wanted to take apart a muffin fan and rewind the stator coils to suit my needs. However, there isn’t much room inside the core of the muffin fan that I had on hand (1.25watt fan) and the number of turns I would need to reach charging voltage would require a smaller wire than I had (or so my professor thought). I took his advice for a lot of reasons (mostly because of a time deadline).

My group member and I mounted his small fan blades on a motor in my room and decided to just give it a shot. After a quick test on the multimeter we achieved about 19 volts (no load) so we threw an automotive blinker lightbulb on it.

Automotive bulb attached

Here are the results: Micro Wind Turbine Test