T Nation

Perpetual Motion

Allright I need some techies to answer something for me.

Hurricane season is comng up and in the Gulf Coast generators are in big demand. I was considering building my own and was curious if this would work.

I was going to take a standard alternator, 12V, 140 amp. and have it powered by a small gasoline engine to get it rotating. After is began to rotate I was going to use it to charge a deep cycle battery. Then run the battery to an AC/DC convertor. The power coming out of the convertor will be used to power necessary items durring power outages, refrigerators, and radios. After the alternator is charging, I was going to take a leg of power from the alternator to power a 12 volt electric motor,it will be used to power the alternator after the gasoline engine is shut off.

Does anyone here with any mechanical aptitude think of any shortcomings this set up could develope or have anything to add?

I think it would work in theory,

Bullpup

You’re still losing power as resistance in the wire, alternator spinning, and a hundred other places. Would it run? Sure, why not. Will it be perpetual? Absolutely not. You’d likely use less power just running the gasonline engine all the time instead of charging and discharging a battery. (a notoriously wasteful process)

You must be kidding right?

[quote]vroom wrote:
You must be kidding right?[/quote]

Why would I be kidding? With the shortage of gasoline and power being out for days.

If I could use the proper pulley from the 1/2 horsepower electric motor to spin the alternator at the correct RPM it should charge the deep cycle battery at a rate greater than the amount it is using.

You’d be a billionaire if you did it.

Homer: “LISA! In this house we obey the Laws of Thermodynamics!!!”

[quote]
…it should charge the…battery at a rate greater than the amount it is using.[/quote]

I don’t know much about electrical engineering, but is your system based on the premise that if you charge this battery, you get more energy out of it than it takes to charge it? Seems implausible to me.

As a previous poster noted, you’ll get energy feeding back into the battery, but due to losses (to appliances, to resistance, etc.), less energy is going to go into the battery than come out of the generator. And, as you know, more energy goes into the generator than goes out of the generator. So if you use the residual energy in the power to keep powering the generator, your system will just die off.

What does thermodynamics have to do with it? I’m trying to convert mechanical energy into electrical energy and then back to mechanical energy using off the shelf items.

Bullpup

Yeah, we have an energy crisis because the entire planet is too stupid to suck free energy out of a device like this to power… everything, for free.

Come back after a couple decades of learning, not education, but learning.

[quote]vroom wrote:
Yeah, we have an energy crisis because the entire planet is too stupid to suck free energy out of a device like this to power… everything, for free.

Come back after a couple decades of learning, not education, but learning.[/quote]

Are you trying to imply that I’m worried about an energy crisis? It’s a crisis but it has more to do with natural disasters. This is a brainstorm I had to produce efficent electrical power while conserving any gasoline that you had available.

Granted you would never have to deal with the possibility of a hurricane and power outages that could last weeks as well as waiting hours in line for gasoline.

If you have nothing constructive to say about an idea that could become a usefull tool when needed please refrain from posting ignorant comment about ones education and or experiences.

Bullpup

[quote]blooey wrote:

…it should charge the…battery at a rate greater than the amount it is using.

I don’t know much about electrical engineering, but is your system based on the premise that if you charge this battery, you get more energy out of it than it takes to charge it? Seems implausible to me.

As a previous poster noted, you’ll get energy feeding back into the battery, but due to losses (to appliances, to resistance, etc.), less energy is going to go into the battery than come out of the generator. And, as you know, more energy goes into the generator than goes out of the generator. So if you use the residual energy in the power to keep powering the generator, your system will just die off.[/quote]

If the alternator output is greater than the load required by the convertor than it should work with out fault, but there will also need to be a regulator in place or the alternator could burn out internally.

Bullpup

[quote]vroom wrote:
Yeah, we have an energy crisis because the entire planet is too stupid to suck free energy out of a device like this to power… everything, for free.

Come back after a couple decades of learning, not education, but learning.[/quote]

Nan-in, a Japanese master during the Meiji era (1868-1912), received a university professor who came to inquire about Zen.

Nan-in served Tea. He poured his visitor’s cup full, and then kept on pouring.

The professor watched the overflow until he no longer could restrain himself. “It is overfull. No more will go in!”

“Like this cup,” Nan-in said, “you are full of your own opinions and speculations. How can I show you Zen unless you first empty your cup?”

Moral: The learned (conditioned) mind has less room.

The alternator to the battery to the invertor sounds fine, but inefficient. The trouble is the alternator running itself with a 12v motor.

The power to run the alternator will always be more than the power you get out of the alternator. (That’s where the laws of thermodynamics come into play; conservation of energy.) The reasons it’s always greater are 1) alternators are not 100% efficient, that is 2) there is always friction in the mechanical parts, 3) there is always resistance in the wires. The input energy = the output energy plus the losses due to friction and resistance. The losses show up as heat.

Also, invertors are very inefficient, so if you can drive a generator directly you are better off.

If you’ve got a big battery, why not charge it up using solar power before the storm?

Why not just use the power from the generator to split the hydrogen and oxygen in water through electrolysis, then feed it back in to the carburator of the generator as feul, which would in turn power the generator…

Just use some exotic materials that have very little impedance near absolute zero, badda bing- badda boom, there you have it.

Just kidding.

I used to work for a patent company. The design you put forth used to come across my desk once a month, sometimes twice, allways rejected.
No conspiracy, just can’t break the laws of physics.

[quote]bullpup wrote:
Are you trying to imply that I’m worried about an energy crisis? It’s a crisis but it has more to do with natural disasters. This is a brainstorm I had to produce efficent electrical power while conserving any gasoline that you had available.[/quote]

No, I’m trying to imply that if such a [insult] idea were possible, it would already be done. The entire [expletive] world could be powered by a system that ran in perpetuity generating more power than it consumed.

Yeah, natural disasters only happen to you personally. Nobody else has earthquakes, tornados, volcanoes or other disasters. Granted, Canada doesn’t have a history of them, but you never know what might happen.

[quote]If you have nothing constructive to say about an idea that could become a usefull tool when needed please refrain from posting ignorant comment about ones education and or experiences.
[/quote]

Ahahahaha. A useful tool? You fool.

You are solving the entire worlds energy needs with this little “device” of yours. You are creating energy out of nothing, magic if you will, which nobody, throughout history, has ever achieved.

How can anyone ever have anything constructive to say compared to that? Just ignore the naysayers, build it, and less us know when you are the new utility company for the world.

[quote]Kailash wrote:
… absolutely nothing worth reading…
[/quote]

Kailash, I hardly qualify as someone with a closed mind. You sit and stare at your filling teacup for your entire life if you wish… eventually you might find you will run out of tea though.

Good stuff.

Honestly, I cant think of anything to say here. This thread cracks me up.

[quote]vroom wrote:
Kailash wrote:
… absolutely nothing worth reading…

Kailash, I hardly qualify as someone with a closed mind. You sit and stare at your filling teacup for your entire life if you wish… eventually you might find you will run out of tea though.[/quote]

You don’t want your mind so open your brain falls out.

my gf brings up a good point, you could replace the alternator with a standard surge protector that is plugged into itself and use that to power your house.