How Many Volts to Run an Electric Car on a Generator?

by William

If I can come up with something that produces electric power for a car motor, how many volts would I need to keep it running?

Hi, William -

You're asking how to eliminate the battery pack, right? The short answer is "I don't know." Anyway, I've only seen generators sold in terms of the number of kilowatts they produce, not volts. That will depend on the voltage of your EV system, I guess.

So here's the problem to solve if you don't want to use batteries:

Generators tend to run at a constant rate, not a variable rate. Electric motors that run electric cars need a lot of power available for acceleration and hill-climbing; this is why people keep the battery pack.

A small generator provides too little power for acceleration, a large generator that provides enough power for satisfying acceleration wastes a lot of electricity when the car's just cruising along at speed. What people usually do is go with a smaller, lighter generator that can charge a battery pack for range-extension (like the Chevy Volt, for instance).

Grid juice is way cheaper than generated-by-fuel electricity, so plugging in is popular.

Best of luck with your project!


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Runner a electric car without a battery
by: Anonymous

I know how to make volts to run electric cars without the use of a battiers. I was an inspector on gas turbine engines for 39 years,and came up with a model that gave me the power to run the engine for an electric car for ever without a battery.

Battery, generator, alternator
by: hdillow


I am a newbie when it comes to electic motors for propusion. I am wanting to repower a boat to use an electic motor, instead of an ICE. My first thoughts, having worked on cars when I was teenager, are as follows:
1. replace ICE with a 60-100 hp electric motor.
2. run the motor from batteries only.
3. Install a generator or a series of alternators to keep batties charged.

I would still use some sort of a ice to run alternator\generators. I am thinking a 10hp-18hp engine should work.

I am thinking this plan would be relativly inexpensive.

I would be very interested in other peoples thoughts.

Please feel free to email me at


Accumulated loss
by: Jerry Halstead

If the questioner is really considering foregoing a battery pack I'd suggest giving up on the whole "electric" idea in general.

Remember, each and every stage of power conversion, be it electrical or mechanical, is a point of power loss. Going from standard car with a gas engine that drives the transmission to a gas engine that runs a generator that then powers an electric motor you will be wasting more gas to obtain the same amount of forward motion.

I get a fair number of people on my site thinking a generator is the way to go because they can run it for hours on a gallon of gas. They aren't taking into consideration the difference in loads and, as you mention, frequent demands for very heavy current.

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