If you haven't noticed at $75/bbl it ain't so cheap these days, and if we use more it will also be more expensive.
$75 a barrel is cheap, and it comes out of the ground for a buck a barrel, (in the middle east.) It will get very much more expensive before it is all said and done.
We can make petroleum for $80/barrel, but cannot take advantage of those technologies as long as our prices can be undercut.