"How is that not better than a car full lead core batteries and gasoline generator?"
It's an illusion created to please the "green" crowd. Diesels are percieved as "dirty."
There were special edition, high mpg Honda Civics in the eighties that got 52 mpg with unleaded gasoline, too.
The ultimate hybrid would be a small displacement diesel, low horsepower but high torque, combined with electric engines at each drive wheel. You'd likely see EPA numbers at or above 75 mpg with such a setup. Only question would be the automatic shutdown and restarting of a diesel, particularly in very cold weather.
So we would be driving locomotives. Cool!
"The ultimate hybrid would be a small displacement diesel, low horsepower but high torque, combined with electric engines at each drive wheel."
I'm with you on that...
At one time there were any number of jap and euro automobiles that delivered a decent ride and 35-40mpg. They all had 1-3,1.5 liter engines, but the engines were high compression, high revving little buzz-bombs that required premium fuel (I am thinking of a whole string of FIATS, Peugeots, VW Rabbits, etc.)
They were killed by emission regulations which could only be met by dropping the compression ratio, crash regulations that raised vehicle weights to the point that bigger engines were needed to move them, etc. etc.
New cars are engineering marvels and fast as the dickens with their hot 3.5 liter DOHC V-6's, hot 4-cylinders, both with variable valve timing. I drive an old MB 300E, which certainly isn't a slouch, but I am blown off the road everyday by Honda Civics signalling me out of the way and doing horizon jobs on me when I am on cruise control at 75.
So maybe we can borrow an idea from the (cough cough) the French, and tax horsepower, or the (harumph harumph) the Italians and tax displacement. In the 60's , 0-60 in 10 seconds was considered mindblowing. But nowadays, the standard is 6 seconds and below. I don't believe that "Speed Kills," but I do believe that excessive speed wastes gas! E.G., my trusty Benz will get 22mpg at 75, but 28mpg at 60mpg
With smaller engines, fleet averages could go substantially upwards. I do love the hybrid concept, especially the plug-in hybrids. BUT, they simply are not cost-effective. It takes a decade to recoup the original cost and that's not counting battery replacement, which is a coupla grand at least.
My ideal solution? No emission regs at all on cars under 1.5liters. Sure their ppm of pollutants is greater, but there are far fewer millions of parts.
At some point in the 1980s, the EPA started downrating highway fuel economy by 22%. I don't know the exact year this started, I have been unable to find it. The EPA's fueleconomy.gov website just says they started doing this in the 1980s.
I did the math and a 2004 Chevrolet Malibu that the EPA says gets 34 highway MPG would have gotten an EPA rating of about 43MPG if they hadn't downrated it.