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Well lets see. Gasoline engine 2% efficient Electric engine over 90% efficient.
makes perfect sense that electric motors use far less energy they are far more efficient.
Only about 20% of the energy from gasoline is extracted and about 90% of that is HEAT and some of whats left is lost in friction.
So what you end up with TO THE WHEELS is single digits efficiency and LOW single digits.
The most efficient gasoline engine is 50% efficient at converting energy to motion and its a diesel engine larger than your house :-)
Potential energy in gasoline is irrelevant. how MUCH of that energy your able to put to work moving your car is relevant. With gasoline very very little of it goes to moving your car. Most of it goes right out the tail pipe the rest goes into heat and some goes into friction. Whats left moves your wheels.
An electric motor IIRC is about 95% efficient at converting its input power into motion and that can be further improved upon.
GRID to WHEELS EV's are about 86% efficient. (compared to 24% for hydrogen fuel cells)
Even motorcycles are NOT very efficient. the only reason they get such high mileage is that drag to a small degree and mass to a massive degree are dramatically reduced allowing you to use a much much smaller engine.
my 82 Goldwing only gets about 30-35mpg then again its 25 years old and has a giant 1.1liter 4 cylinder engine and masses 900 pounds :-)
Compared to a 200 pound 250cc scooter which can nab 70+mpg
One of the reasons GM's EV1 got such amazing range NIMH or not (even the lead acid version got 60-80 miles to a charge sometimes 90miles) was that is was very CLEAN aerodynamically and it was VERY light (aluminum chassis plastic body etc..)
If you make your engine to run at one speed its not an engine anymore persay its a generator either way it won't work. Except in Arizona nevada and kansas etc.. there are no FLAT roads on this planet. they all have gradings up and down turns curves hills etc..
Next time your driving get on a flat and notice how you can keep the gas in one spot to maintain speed. NOW keep the gas pedal in that spot no matter what. see what happens when you hit even a small incline. you will lose 5-10-15mph or more if you do not compensate with "more gas"
this would not effect a genset arrangement. It never touches the hill. you would simply use more watts from the battery pack when you hit that incline.
Your motorcycle pusher would be very efficient but no where near as efficient as a serial hybrid setup. (that is what using a generator to keep a battery charged is)
It takes about 8000 watts to go 100 miles in a lightweight EV like the EV1
about 10,000 watts in something like say the Rav4EV
do the math from there. My generator can run 11 hours at 50% load that means I can generate 27,500 watts for 5 gallons of fuel. (thats conservative mine has gone over 12 hours at 60% load but lets use the manufacture rating just to be easy with the math)
that means IF I had a battery pack and IF I had a way of integrating it with the genset to keep the battery charged up while driving in theory I could go 340 miles on 5 gallons of gasoline
That's 68mpg and thats not even counting using the power in the batteries after the genset is out of fuel. if they can get me say 40 miles (average lead acid EV range) thats 380miles or 76mpg
Not bad ehh. and in theory you would only need to use the genset if you know your going further than the range of your battery pack.
this would be pretty harsh on the batteries though I would imagine. Not sure how well leads would take being charged and discharged at the same time rapidly.
Now you may have noticed a problem with these numbers. the 27,500 watts is over 11 hours. going 340 miles on the highway will used 27,500 watts in 3.4 hours. Wee problem there :-)
Depends on how many watts you use CRUISING and if there is enough surplus watts to replenish the battery pack while cruising. I am guessing you would really need at least a 10,000 watt generator to make this work and probably end up around 60-65mpg
The point of a genset arrangement is not to be your final car. its to allow you to have an EV if you need MORE than the 40 mile range a lead ev can currently give you. Later on down the road once the patent expires and they start making NIMH's or when a cheaper alternative comes along you UPGRADE the battery pack and eliminate the Genset.
alas its a lot more complicated than I thought. I have NO idea how to integrate the 3 systems to make them behave with each other. Somehow I don't think you can just plug the generator into a bunch of chargers and connect them to the batteries.
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