Re: PHEV information
Let me try to referee if I may.
#1 Comparing Diesel Locos to Steam Locos is a bad idea. I have been an avid railfan for 30 years. Steam locos were actually more powerful, and more capable than any diesel loco ever built. EVER. ( like 5 to 6 times more powerful ) And the fuel economy was fair.
ONE 1945 steam locomotive can pull 150 loaded coal cars.
One 2008 diesel locomotive can pull 25 loaded coal cars.
Steam locomotives were also, a mechanical nightmare.
They required daily maintenence. Not monthly!
In 1945 there were more locomotive mechanics, than engineers.
Diesel locomotives are quite large, they are not "one-third the size" becuase of the electic drive. A 1000HP electric drive motor will require a 1200HP diesel motor due to losses. Modern locos are diesel electric because the diesel can run at max. RPM/Horsepower when the train is standing still or crawling, and there is no "transmission" or gear shifting.
#2 I have never met Stan. I do not know Stan. Stan is not paying me to type this. However, Stan is most correct as I see it.
Electric motors are much more efficient at turning energy into motion, which is why you buy a car. HOWEVER any electric motor that is spun with power from a gasoline engine ( aka FEH, Prius ) is never more efficient than running the gasoline engine alone. This is due to the commonly cited, but sometimes not fully understood "laws of physics, nature" etc.
So why are hybrid cars "more efficient" aka get more MPG?
#3 Timing is everything.
It is MUCH more about TIME than watts, calories, joules, btu, or "noodles".
( Nice try, and I applaud your effort, but I don't care for noodles. )
Let me say it again... TIMING IS EVERYTHING.
Hybrids don't get more MPG because they have an electric motor. Really.
They get more MPG than regular cars, because regular cars do zero work when the tires are stationary. The TIME spent at stoplights uses gas, but does zero useful work in a regular car. The TIME a Hybrid spends at a light with ICE on does useful work. It charges a battery, which in turn, can produce work for you later ( taking off from the light). The TIME a regular car spends coasting downhill burns gas, but does zero useful work for you ( assuming the hill is steep enough for gravity to do all the work ). When a hybrid is going downhill, it is often doing useful work, charging a battery for you. When you hit the brakes in a normal car, the brakes make heat, and that heat goes into the environment. The car's brakes do zero useful work ( scientifically speaking ) for you. They are useful, but literally, they are not doing work for you. In a hybrid, the brakes do useful work for you, they charge a battery.
A hybrid is not Not NOT more efficient because of the electric motor. Nope. The hybrid is more efficient because it has a storage device ( battery ) other than gasoline. The hybrid is more efficient because it has a downsized ICE. The hybrid is more efficient because literally, it uses it's time wisely.
If you had a big lead ( lead is massive ) flywheel, and the ICE spun-up the flywheel when you were at a stoplight, or when braking, or when going downhill, you could discard the battery, discard the electric motor, and probably ( almost certainly ) have an ICE car that was more efficient than the one you have now. Just a battery fits into a more convienient package than a giant lead flywheel.
A hybrid is more efficient because the ICE is doing useful work a high percentage of the time, ( aka little idle time ) and a regular car is doing useful work a low percentage of the time ( lots of idle time).
Quote:
"a small efficient Diesel driving a generator which runs the electric motor as being something worth looking into. You would use the battery pack to add power for starts and hills and passing. Otherwise the genny would power the motor."
This is ALWAYS ALWAYS ALWAYS going to be worse fuel-wise. The senario you diescribe will consume significantly more fuel.
Instead of a diesel motor spining your tires, you now have the same diesel motor spinning a generator, electric motor, and wheels!!! This is impossible to be more fuel efficient... and this is why you don't see one on the road today... it would be easy enough to build. What you describe, like in a diesel locomtive, gives you a mechanical advantage ( aka torque multiplier ) but a fuel economy dis-advantage.
Quote:
"If it takes 1/4 gallon to go 10 miles using the ICE ONLY and this is due to it's inherit inefficiency I think that those same KW's "
You don't have kW's. You have gasoline.
are better put to use in powering an electric motor which even being charged by the ICE will go farther due to it's HIGHER efficiency."
False! What you describe would only work if you had a chemical fuel cell, where you went from liquid, chemical gasoline directly into electricity. Any time you "burn" this gas first in any combustion engine and turn it to mechanical energy first, and electicity second, it will always be less efficient, not more.
You must multiply all the steps. And when you multiply percentages, the net result gets smaller, not larger.
Take a 25% ICE and 90% efficient battery, 90% generator, and a 90% traction motor.
Take 100kW of gasoline equivalent.
You could use the ICE only, and put 25kW to the wheels.
OR
You could use 100kW of gasoline equivalent and spin a generator, which charges a battery, which later is used to turn a traction motor.
You have 100kw x 25% x 90% x 90% x 90% = 18.2 kW to the wheels. You are saying this is more efficient than putting 25kW to the wheels with an ICE direct drive to the wheels???
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