can car alternator generate power without battery,please help?

i want to generate power without battery if its possible

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purelabor5 years ago
Brushless alternator that can handle rpms.
Battery is needed as a shock absorber for electric charge. But you can use a small type battery.
IknowIt7 years ago
Oh yeah and for those who think that an alternator wouldnt last long at high rpm... ever heard of race car driving? they can scream around them tracks all day and year without replacing the alternator. You just have to make sure you have a good one as I mentioned before
That's cuz most people who race short, high RPM races actually turn off their alternators with a switch in the car. Dragsters often don't even have them.
IknowIt7 years ago
Yes you do have to "excite" the alternator and I would recommend using a performance alternator if you want to peak it to high rpm. Using a fan blade on it will help cool it down too.
lemonie8 years ago
Yes they're self-exciting. L
mikebassam (author)  lemonie8 years ago
thanks but someone told me that I need to connect a battery to the alternator to excite it ,is that true
I don't believe so, but I guess it depends upon the model to some extent ( link])

mikebassam (author)  lemonie8 years ago
thanks for your help, will i damage the alternator if i run it lets say 20000 rpm?thanks
no way, most cars redline their engines at between 5000 to 8000, i would't expect a alternator to last very long at those speeds, and at 20,000 it would probably destroy its bearings and the alternator would most likely turn into shrapnel.. .
Mmm - is it designed for that I wonder? (Thinks car engines rev-range) 20,000 sounds a bit extreme - how would you drive it that fast!? L
IknowIt7 years ago
Yes You can generate power without a battery or any kind of power source. The only down fall to this is the more power you want to use ( appliances ) the less output you will get from the alternator (Otherwise we would have had perpetual motion if it didnt). If you would like to know how to make this simple device to generate your own power let me know
climber14997 years ago
I certainly do not agree with the above comments. People are mostly ignorant of the advancement in Science and technology and tend to rely and use whatever they read years ago.

Use Permanent Magnet (Brushless, neodymium magnets) Car alternator to generate electricity for home, even entire home (requires 2 or more),  which does not requires a battery to run and can generate electricity even if turned with hand. Use a Grid Tie Inverter to generate AC electricity with Pure Sine wave (if the alternator is not equiped with a voltage regulator but produces DC volts )or use a good inverter if the alternator is giving 12VDC with high amp. Anyone with objections may please post.
DocMagnus7 years ago
A bit old as far as replies go, but will help others looking for the same answer I hope =)

What's an alternator? As stated by others in this post, it's a generator. An AC generator to be precise. Does it have magnets in it? Nup! And there in is the answer, can you use it to generate power without a battery. No, you can’t as it needs to be 'loaded' to work. You can start a car, remove the battery, and drive around the block until the alternator gives up the ghost. Don’t try it though, it will die without too much distance =)

As touched on, an alternator generates AC current (alternating current - hence the name.) You CAN use it to generate electricity though, as the unit has diodes built in, and a bridging rectifier to keep the energy flow in one direction and convert it to DC. The job of the regulator (in a car) is to regulate the voltage to meet the needs of the battery and keep the volts at approx 14.4. Increase the load on the battery, and the regulator draws greater load from the alternator to keep up the voltage.

Running the alternator at about 3000 rpm is considered optimal for most units. Less than 2000 and they 'generally' have trouble sustaining decent energy flow. this is in the case of a single phase unit. A 3 phase unit develops more power sooner. More than 5000 will see heat issues creep in. Which is why older units have fan blades on the outside of the unit (attached to the inner pulley.)
I set up a largish windmill some years ago (around 3 meters in diameter) and ran a three phase on a step up pulley (large spindle on windmill, small on alternator) and connected it to a bank of 6 truck batteries. I used a regulator straight out of a car from the wreakers (same place I got the alternator) and it did the job perfectly. Kept the battery bank charged and powered small house (via a rectifier) pretty well for lights, tv and a few other must haves. It ever did the water heater if you gave it time to warm up.

So the answer to your question, is no. An alternator cannot 'sustainably' generate power without a battery as it uses the back load to generate the electromagnetic field needed in place of the magnets in a generator.

Hope that clears things up for you - and anyone else who reads this =)
No. The rotor, which is an electromagnet, needs a current to make the field that cuts the stator coils. You could try replacing the rotor windings with suitable magnets taken from a few discarded speakers. Not an easy job. ~Bob~
rickharris8 years ago
The alternator is driven by the car engine and generates AC electricity at about 14 volts. If you turn it it makes electricity.
skunkbait8 years ago
Yep, If the car's running, and there's nothing wrong with the alternator, it'll crank out juice.
orksecurity8 years ago
The alternator is a generator. If you can keep it turning, you can get electrical power out of it. Of course something (you?) has to provide the power to turn it; there's no free lunch.