powering turbine generator using a fan

Using a fan; can you get more output to power a turbine generator; using a large cog (like a star on a bicycle wheel).To power a bike you have a large star in the front and a small one in the rear which generates more power. So can you do this to power a turbine generator using a fan?   

mannymanster (author) 4 years ago
“Now this is what I am asking”, say you place a small cog (star) on the turbine generator, and on the large cog (star); you place fan blades. You connect the two stars with a chain, just like on a bike.
Then you have a fan facing the blades on the large cog (star), so when the large cog spins, the smaller cog should go faster.
My question is using a fan on a turbine generator, in the why I just explain; can you get create perpetual motion?
A couple of years ago I’ve done experiment using a small electric motor, battery operated plastic fan, rubber bands, some plastic pulleys.

I got the motor from a toy car, and the pulleys from an old weight lifting bench. The fan was one of those nine volts you held in your hands to keep your face cool in the summer.
I took it apart connected some wire to it.

It took me a sometime get going; it would work for few minutes then stop. I tried different size wheels, some from toy car; others anything lying around.
One time I had work for ten hours; really ten.
After that I gave up, I haven’t stop thinking of it.
So think if I get the right size generator, with the right amperage, I believe I could get something going.
Maybe using a fan belt, anyway I’ll keep posting and let you all know what the outcome.
jkimball4 years ago
I look forward to your experiment.

It seems that your question is equally about gearing as it is about wind power.

As you point out, when you connect a larger gear to a smaller gear, the smaller gear spins fast to match the rotation of the larger gear. You can see that on a bicycle, where they are connected by a chain.

In your experiment, you plan to do the same, except instead of connecting the two gears by a chain, you will use fans and turbines to connect them.

Try to build a model using bicycle parts first, I think you will find it easier to work with than the fans and turbines.
bwrussell4 years ago
Nope, perpetual motion is not, and never will be, possible. You have a fan powwring a fan, that will never be 100% efficient. And where does the power for the second fan come from? Unless it's powered inside the system you can't have perpetual motion.
What about friction loss in the chain and turbine and heat loss in the turbine? Check out some articles, even Wikipedia, on the laws of thermodynamics for a better explanation of why perpetual motion is impossible.
bwrussell4 years ago
You can't get more out then is put in if that's what you mean.

There are always trade-offs. When a bicycle reduces to a low gear it requires less force on the pedals to turn the wheel but you have to turn the pedals more often and you go much slower. I don't think you would be able to generate any pressure in the turbine due to the reduced speed.