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In the end, volts, amps, it doesn't matter. Watts is power. You can use volts and amps to derive watts; amps * volts = watts... If you heard that someone can power a vehicle down the road on just 0.8 amps, and let's assume 15 hp for something like a Civic @ 55 mph:

15hp * 750 = 11250 watts

watts = amps * volts, so: 11250 watts / 0.8 amps = 14062 volts

14062 volts, not very realistic. But something more realistic would be:

11250 watts /

**80**amps = 140.6 volts. So in this case, 140 volts is needed to power a Civic at 55 mph (15 hp), while pulling 80 amps. Much more in-line with a conventional EV conversion.

The relationship is simple. Look at it another way. What about a 36 volt system? That's 11250 watts / 36 volts = 312 amps. A lot of amps, but it can be done if the batteries can handle it.

A 300 volt system? 11250 watts / 300 volts = 37.5 amps.

So there you go, the higher the voltage, the less amps are needed to create an amount of power. The lower the voltage, the more amps you need to create the same amount of power.

At 55 mph aero drag is a big concern. Some vehicles will consume more than 15 hp maintaining it, while more aerodynamic, lighter vehicles will consume less. But 1.2 hp? Nope... Very light, aero-sheathed, recumbent bicycle maybe...

Let's look at your second posting.

Open Guy is claiming 100 amps out of a 5 hp generator. That's 5 hp * 750 = 3750 watts. 3750 watts / 100 amps = 37.50 volts. There's your "36v" system. But it's still only 5 hp.

You researched a 2300 watt generator @ 120v. That's 2300 / 120 = 19.17 amps. Sounds like almost 20 amps (which is what its rating was). But it's only 2300 watts / 750 = 3 hp.

Most consumer generators are 120v, because they're designed for household appliance use. A 100 amp generator @ 120v would be producing, 100 amps * 120 volts = 12000 watts. That's a big generator. And 12000 watts is, 16hp. So yes, a 100 amp, 120 volt generator could probably get most of the way to powering continuously @ 55 mph. And I'll bet that generator will be using a 16+ horsepower engine. Probably closer to 20hp due to efficiency losses. See how much fuel that burns in an hour.

Keep in mind that 15 hp is generally what you will need to maintain 55 hp. To get there requires either a bit more, or a lot of patience.