An article in Business Week Online tells us that experimental hybrid cars get up to 250 mpg (a very similar article appeared in the New York Times business section a couple of months earlier). I enjoy reading between the lines of lay press science and technology articles. There was a great discussion in Grist on this subject not too long ago.
Gremban ...spent... $3,000 tinkering with his car... [I]n the trunk sits an 80-miles-per-gallon secret -- a stack of 18 brick-sized batteries... [T]he extra batteries let Gremban drive for 20 miles with a 50-50 mix of gas and electricity.
In other words, for his $3000 he will get 80 miles per gallon for 20 miles before his carriage turns back into a pumpkin. For the rest of the day he will carry a hundred pounds of bricks around in his now-useless trunk, which by the way will degrade his gas mileage. For the first 20 miles he drives each day he will save 0.25 gallons, thus recouping his $3000 in about twenty years, assuming his batteries last that long. The more miles he drives after the batteries go dead, the worse things get because of the extra weight of the dead batteries in his trunk. Which leads me to ask: If his commute is only ten miles each way, why not just ride a bike, get a little exercise, and save $3000? You can also get 80 mpg out of a 40-mpg car by carpooling with one passenger, or get 120 mpg with two passengers, or 160-mpg with three passengers.
