That brings up an interesting question, much of Europe has gone diesel. Granted, it is not a "green" fuel, but it is much more efficient than gasoline and has been just as clean as gas for quite some time. In the early 80's some US manufacturers such as Cadillac tried to offer a diesel and failed miserably at it. I wonder if that has something to do with the US avoidance of diesel in american cars over here. Also in Europe diesel is cheaper than gas.
On average, sure. But it depends. It's not that much cheaper;