All of the stuff you're talking about seems to be "perpetual motion machines of the first kind" (more power out than in).
This is prohibited by the principle of conservation of energy (along with its special case, the first law of thermodynamics).
You have to have an external source of energy great enough to provide the output plus all the internal losses of your system. Otherwise your system is just a glorified battery or spring. It provides a little power that had been stored in it when it was built, then runs down and stops.
This is true NO MATTER HOW COMPLICATED YOU MAKE IT. There is NO free lunch. Every transformation of power loses a little bit, none of them EVER give more than they take.
If this weren't true, we could do something like hook the shaft of a motor to a generator, hook the wires of the generator to the motor, wrap a cord around the shaft and yank to give it an initial spin, then pull off the "over unity" part of the power forever while the rotors spin away merrily. If there were EVEN ONE energy transformation that gave more than it took, we could combine that with an efficient transform in the other direction and do the same sort of thing - pull off the excess and convert it to a useful form. But there isn't EVEN ONE such transformation.
All the stuff on this board (along with all the stuff in power engineering) is about CONVERTING one form of power to another. You take wind, water, light, heat, fuel and oxidizer, or energetic nuclei - from an EXTERNAL SOURCE - and turn part of the energy in it into some more useful form. Then you dump the slowed air, lowered and/or slowed water, waste light/heat (at a lower temperature or longer wavelength), chemical exhaust, or nuclear waste somewhere ELSE and replace it with fresh input material.
Sorry, but that's how the universe is apparently put together.
In the unlikely event that there IS some way to break this fundamental law and get "over unity" energy conversion, expect it to show up first in some obscure branch of extreme-condition physics, in experiments run by a lab full of serious experts using horrendously expensive equipment, not from garage mechanical tinkering.
Which doesn't mean there's nothing useful or fun to do. But you'll always need to find some external source of energy to run your contraption.