You nailed it Billwald. It is my understanding; however, correct me if I am wrong, that when the gasoline engine kicks in it actually feeds mechanical power to the wheels and does not make electricity the way trains do.billwald said:Internal combustion engines can't excede their theoretical efficiency which depends in part upon the compression (ACTUALLY EXPANSION) ratio of the engine.
Each time energy is converted from one form to another there is a conversion loss thus converting gasoline to mechanical to electrical and back to mechanical must introduce inefficiencies. The hybrid seems to be more efficient because the engine doesn't run and stop at every stop light and because of the regenerative braking. Drive your hybrid across Montana or South Dakota at 75 MPH in the summer and see what your mpg is.
So, therefore your losses aren't quite so bad and since a lot of energy will come from your extension cord at home, most folks won't pay much attention that their electric bill is being used in exchange for gasoline.
You are right in driving across states, hybrids are best designed to be driven in cities where it is stop and go. This way the dynmic breaking works well. It is my undestanding; however, that the cars are build for high effeciency to start with, although performance suffers because of it. ...and as you pointed out, there is only so much effeciency thaat you can obtain from an internal engine of a certain size.
The bottom line, the hybrid makes a great commuter car if you live in an area where you have to deal with traffic. At this point in time, you can find a standard car that can give you better highway mileage.
This technology is still in its infancy. We have a long way to go, but our engineers are not dummies, so newer and better alternatives will be coming out. Again, for those of you new at this go to the department of energy's website for lots of information related to alternative fuels such as liquified natural gas, hydrogen, ethanol and many others. It gives many scientific reports and gives pro's and con's.
I had a man today who was griping about why we didn't just use ethanol. I had to explain to him that anything more than about 10% in the gasoline will strip the lubrication oil off of many of the components causing extreme engine wear. So, you can see, all of these items are not just simple replacements. Plus, hydrogen, the absolute cleanest fuel has a problem of having to be stored at extreme pressures in order to carry enough to go anywhere. There is promise of a material that will abssorb hydrogen and let it out at about 5 PSI (Don't remember the exact number). This means the tank does not have to handle 2000 or more PSI making it much safer in a wreck. It still burns wickedly and most often hydrogen flame are EXTREMELY dangerous because they cannot be seen and a fireman can walk right into the blaze. If hydrogen is involved the procedure is to carry a cloth mop in front of you in case you get close to the flame front.
Boy, there I go rambling. I guess you all know by now that I enjoy my engineering.