Steve Clunn wrote: > Lee will you put one your car so I don't feel so alone?
Yes, I certainly will! >> And what about doing both a solar panel and a mini wind turbine? I like the idea of something that moves (or at least has blinking lights). If it's a solar powered hood ornament, then I'd include wheels that spin, or lights that blink, or a moving sign LCD display or something. Perhaps a little EV car on the hood, whose wheels spin from the sunlight falling on it. > small computer fan... that almost sounds to big; hope we don't need > somthing that big to run a meter. The power you get from the wind is proportional to the swept area of the blades. Large ones deliver around 400 watts at 20 mph from an 8 foot diameter set of blades, which is 8 watts per square foot. At this rate, a 3" propeller would produce 1.5 watts. Someone may have some better equations or rules of thumb for such tiny wind turbines. Toy motors are likely to be less than 25% efficient, so you'd be doing good to get 0.4 watts of electrical power. That would easily run a multimeter (9v x 10ma = 0.09 watts), and is plenty for recharging 9v batteries or AA cells. A big problem is that the propellers spin relatively slowly. Most cheap motors are meant to run at high speeds, and generate very little voltage if spun slowly. That's why the 120v motor I tried did so much better than the 3v and 12v motors. > These motors are everywhere. The electric jeeps that are for kids have > two nice ones, although they may be too big. Yes indeed. They would be suitable for a much larger propeller; maybe a foot or more in diameter. Seems overly large for a hood ornament. That big starts to get dangerous for pedestrians. Rick wrote: > I just don't want the thing blowing off the car because it catches too > much air. Either a magnet mount, or a clip that reaches around the front lip of the hood will work. They sell them as no-hole mounts for antennas. Evan wrote: > Hi Lee, how about a "motor pod" for model aeroplanes - there > used to be several balsa kits for which you could buy a clip-on > motor/battery/propellor module, made of aerodynamic red plastic. I've never seen one, but it sounds ideal! > If you want to generate useful amounts of power, I would suggest > a bicycle dynamo with a high-pitch multi-blade fan. Bicycle dynamos are high-speed AC generators, and not particularly efficient. But they might work with a fan that can spin them fast enough, or a transformer to step up the voltage to something useful. -- Lee A. Hart Ring the bells that still can ring 814 8th Ave. N. Forget your perfect offering Sartell, MN 56377 USA There is a crack in everything leeahart_at_earthlink.net That's how the light gets in - Leonard Cohen
