Wind Power

[MasterAlex]

You will not be getting any free energy. If you are slowing down and not using any power besides momentum you will be gaining energy, some of it at least, that you lost while accelerating. It's like the regenerative breaking on hybrids, except with wind power instead.

[Cd]

I didn't read all of the postings here, so I may be repeating someone .... but .... I saw in Popular Science circa 1999 - 2000 that a company was experimenting with this idea.
A 'windmill' was placed on the roof of a van sideways. As the vehicle drove along, the wind would spin the blade and produce electricity.
What made their idea so clever was that the blades flattened out as they spun around creating far less drag than if they remained intact.

It was the issue that had "Detroits' 80MPG supercars". ( The Precept, Dodge intrepid ESX, Ford Prodigy.)

Like so many things in that magazine, it's promises never amount to anything.

[JV-Tuga]

Originally Posted by MasterAlex

I saw a video of a new type of windmill that looks promising and you might be able to put it on the bottom of your car and actually get more energy while driving than you are spending if the conditions are right.

I can't find the link to the video but it was basically just a sting that had magnets on the end that would vibrate up and down when wind was blown on it (like if you take a piece of string and blow on it the string will go up and down). As it blows up and down the magnets produce a charge with copper coils.

I saw the exact same video and immediately thought of using it on a car. There are areas that are not exposed to the wind but still get a lot of movement, like the recesses under the car. Instead of covering the bottom of the car you might try to harness that turbulence, since it already is present and the addition of the, let's call them "power ribbons", wouldn't affect your drag in any way. It would be all gain.

[conradpdx]

Originally Posted by MasterAlex

With a windmill like that you wouldn't get more than 100% efficiency if it was always running, if you could find a way to make it not drag when you are cruising or accelerating and only spin while slowing down or while the car is off (pretty much anytime you aren't using the battery) it could work. I saw a video of a new type of windmill that looks promising and you might be able to put it on the bottom of your car and actually get more energy while driving than you are spending if the conditions are right.

I can't find the link to the video but it was basically just a sting that had magnets on the end that would vibrate up and down when wind was blown on it (like if you take a piece of string and blow on it the string will go up and down). As it blows up and down the magnets produce a charge with copper coils.

Yeah I've seen that video too, problem is that the magnet on a string trick produces very minimal power (less than an amp/hour), even in a strong wind. I doubt it'd be consistent enough to do anything. Not to mention the drag of vibrating strings or the sound it'd cause when encased or near a hollow shell (think one note guitar).

Id did find the concept interesting, but I don't think it'll amount to much. Too many variables. And if it was even remotely practical I'm sure the inventor would at least be working with NATO or some international charity to field test it. After all it's only a magnet on a string with a couple copper washers secured next to it.


<edit> As to the whole concept you also gotta remember that windmills generate a lot of turbulence, and the big ones are suspects in even causing noticeable effects on the local weather.

I doubt it'd even work while coasting in that it'll probably slow you down considerably faster than you'd normally coast which would thus lessen the effects of regenerative braking. At best you'd maybe break even.