Take a Mathmos wind light and modify it to read wind speed using a voltmeter.
Remove the one screw and gently separate the plastic case into its two pieces.Carefully remove the generator and LED’s from the plastic case (they just slide out). The wire from the generator is extremely small and could easily be broken.
Solder a wire wrap wire to one leg of an LED.Solder a wire wrap wire to the other leg of the LED.
Place the generator back into the plastic case. Carefully attach the other half of the plastic case and fasten with the screw.
Attach the two wires to a voltmeter. Set the voltmeter on a low AC voltage scale. 2.5 volts equals about 15 mph. You will not get much higher than 2.5 volts unless you clip the “heads” off the LED’s (then you would lose the pretty lights).
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