I don’t think in Iowa I would need to worry about emissions as we don’t have inspections. even if we did you could leave the ICE off during the test.

The had this to say about his setup

I highly recommend a 36-volt circuit, so you’ll need at least three of these 12-volt batteries. Most cars will draw 150-200 amps at 45 mph. When looking for a battery, compare the reserve capacity and the number of plates per battery. A high number indicates deep-cycle capability and high-current output. One battery I’ve found has 186 plates and a 75-amp, 12-volt output for 100 minutes.

I installed three 12-volt, heavy-duty automobile batteries—in series—“fed” by a 10-amp generator to do that job. The small engine then powers the generator. But I decided I wanted a bit more power in the new pickup, so I decided to forgo another five-hp gasoline engine in favor of a nine-hp diesel. That’s equivalent to about a 20-hp gasoline engine. It turned out to be a perfect arrangement. It has tremendous torque, will bear very heavy loads without stalling, and is incredibly reliable.

A typical 2,500 pound hybrid electric car will require approximately 200 amps at 36 volts to run 45 mph. Using that kind of information you can arrive at the best kind of battery pack for your particular use. For instance, two banks of the 186-plate, 12-volt batteries (six batteries) has nine kwh available. It takes 7.2 kwh to go 45 miles on the open road. With this battery system you should have a good hour of drive time on the batteries alone.

A 25-mile test run using the nine-hp diesel engine showed that a gallon of fuel could produce sufficient amperage at 36 volts to drive the car two hours at 45 mph. That’s 90 miles to the gallon. If the terrain had been a bit less hilly, the average speed would have been closer to 55 mph. It’s important to realize, however that stop-and-go traffic shortens the range and reduces efficiency because of the heavy current draws (600 amps) in taking off. That’s where the surge current (cranking power) of the battery comes in. A great deal of city driving will certainly affect overall fuel economy

Now he mentions

200amp at 45mph

600amps at takeoff

Does this sound accurate?

My thought was a 48V system. Have a diesel motor with 4-65Amp Alternators, each tied to a single battery, but I can’t figure out if this is even possible as I would have to use big diods to isolate each alternator from each other and I would need a floating ground. I’m trying to figure out a cheap junkyard method of assembly.

4-65amp alternators = 260amps

each alternator puts out 14Volts this comes out to a total of (I*R) 910 watts for each alternator X Qty4 = 3640Watss/746Watts= 4.8HP

So if cruise speed at 45mph comes out to 200amps I would have enough juice to keep the batteries alive during long hauls. When I stop at lights I would charging the system.

While looking up data on diesels I found this.

Why diesel-power instead of gasoline? Unlike gas engines, diesels have no spark plugs to replace, or carburetors to rebuild and service. Diesels generally burn less than half the fuel that gas engines do to do the same amount of work. Diesels regularly outlast gas engines ten-to-one. The average diesel engine will run 20,000 hours before needing any service beyond routine maintenance, but many make it to 50,000 hours, and some a lot longer than that. At four hours a day, even 20,000 hours works out to nearly fourteen years! A good spark-ignition engine is about 24 percent efficient, “A good diesel is about 30 percent efficient.

So I would think a good 8hp desile motor would do the trick.

OK so where is the flaw in the logic hear. I know someone on this forume can kill it.