Bottle dynamo generator
High Resolution image here (178Kb)
This design utilises the more readily available bottle style generator (particularly in the U.S), it is still being manufactured by various companies.
This unit has the same power output as the dynohub generator 6V - 3W, however it has to rotate at a much higher speed to reach its rated output.
I used a 320mm Diameter car radiator fan as the turbine, these are ideal as they are very strong and reasonably light. They also
reach a high rpm in windy locations. The fans can be found at car breakers yards for a couple of pounds each.
A nose cone can be created by buying a cheap plastic funnel and cutting the spout off and bunging up the hole.
The existing drive wheel was removed and a 5mm threaded aluminium boss was turned to attach the radiator fan.
Even with a high speed turbine the voltage barely gets above 2 volts, not much good for super-bright LED's.
What was needed was some electronics to push the voltage to a more useful 3.6 volts.
www.coastelect.com supply the ZenGen (previously known as a Linverter) an electronics kit that does exactly this.
The ZenGen powers super-bright LED's from supplies of 0.8 volts to 3 volts. These LED's normally need 3.2 - 4.5v to shine brightly
This worked well, after rectifying the dynamos AC to DC with a bridge rectifier using low power signal diodes, the Linverter boosted
the voltage sufficiently to power the white 4 LED's that were supplied with the kit perfectly.
NEW- I believe the Linverter is currently out of stock, for those of you with some electronic circuits knowledge.
I have included the instructions I received below (click to enlarge) 242kb
See the Video of my modified wind generator design (1.3Mb) WMV format