Alternator to Generate Electric Power for EVs?

by Esam
(Forestburg, TX)

Alternators are AC Electricity Generators

Alternators are AC Electricity Generators

To generate electricity to power an EV, couldn't an alternator of the proper given voltage be used instead of batteries?

Hi, Esam!
Alternators turn mechanical energy into AC electrical energy. If you have an electric motor of some type moving your car, you can recapture some of that mechanical energy (regenerative braking, for example) to put back into the battery...but you can't get a generator or alternator to put back MORE energy than you've already provided.
This is the law of conservation of energy. It hasn't been broken yet, although not for lack of trying!

You could, however, use a gas-powered engine to generate electric power for the car's traction motor; however, without any kind of storage device, you'd need a whopping big generator for acceleration and hills. Half the time your electric car would either be underpowered by your generator (if you chose a smaller one) or the generator would be running at twice the capacity necessary (if you chose a larger one). Batteries provide a place to put the extra juice so that you can choose a generator sized right down the middle.

It's been done.


P.S. Read about a home-brewed hybrid here.

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alternator for ev
by: Anonymous

I think the idea is possible. Most people seem to think of perpetual motion (which is not what is being asked) or conservation of energy, etc. right off the bat without really seeing what is being asked. Vehicles do it now. Your vehicle has a battery that supplies the power to your vehicles electrical loads. That battery is supplied by power from an alternator. That alternator is given power by the engine that gets its power from fuel during combustion. To answer the question, you would have to figure the electrical load requirments (ev motor & normal loads in vehicle) determine hp requirment for given loads, use a high output alternator (zena welder & pulley system;, & then sacrafice some driving hp for charging hp, not to mention friction loss through belts & pulleys. Voltsman01 has some good comments as well. Again, people are simply wanting to do what a mechanical engine is already doing (using some of its hp to turn an alternator, to supply power to the battery that supplies power to the loads). This would beat driving for 2 miles and then having to charge for 12hrs or paying to charge from the new charge stations.

Alternator to Generate Electric Power for EVs?
by: voltsman01

However if you were to take a high output alternator in the 300+ amp range, install a double shafted electric motor, run the alternator directly to the dc motor (The torque of the motor will easily turn the alternator) Connect the alternator to the cars charging unit, divide your battery pack in 2.Each pack drives the car for so long you switch to the other pack and let the alternator charge the idle pack. With no load on the pack the alternator will charge the batteries. The trick is not to charge them too fast or not fast enough. My planned EV conversion is a Ford Probe GT. I originally planned to go with 24 12v deep cycle batteries. If this works I will get the same or better range with only 12 batteries. Significantly reducing the conversion cost and vehicle weight. A win win no matter how you look at it.

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