Originally Posted by soup325
just an idea...
why dont you use an 12V alternator from a small car/motorbike....fab up a chain drive...and bing.....some wires.....lots of juice for lights, sirens, and a phone charger or stereo.
You can use a brushless motor like used on RC airplanes and make the converter to dc and that will charge a small battery. They are using this setup on RC helicopters. Do a Google on it.