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mcsoupman
12-03-2011, 9:42 PM
I don't know squat about anything and am learning all the good stuff on the go here. I have a power/generator question.

Could you have an electric motor connected to a pulley running an alternator that in turn charges the electric motor, then use the motor to generate power for small appliances?

GrizzlyGuy
12-03-2011, 10:13 PM
It sounds like you are describing a perpetual motion machine: electric motor turns the alternator which then powers the very same electric motor(?). Perpetual motion machines are impossible to construct as they would violate the first law of thermodynamics.

smle-man
12-03-2011, 10:19 PM
There is too much loss when generating power to run itself.
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thenodnarb
12-03-2011, 11:22 PM
I think the simpsons did that when they got their windmill. When there wasn't any wind, they just hooked up some fans to provide the wind. The turbine in turn powered the fans.
Yeah, thats a fantasy. As someone mentioned, there are losses at every step and inefficiencies at every step. And if you had electricity to power the electric motor, why not just power the things you want to power?

A better system is to convert energy from one source to another, more usable source. Like diesel from plastic, or electricity from a generator powered by wood gas. Some systems, like the diesel from plastic, produces enough energy to sustain the conversion process, but it isn't creating energy from nothing, its just converting fuel to energy.