Another American trade on auto efficiency?

A lithium powered Escape at Hybridfest

One way or another American automobiles are going to become more fuel efficient. CAFE alone will make America's fleet 40 percent more fuel efficient. And, if another gas price spike happens in the next few years, consumer interest might forever shift towards greater and greater fuel economy.

Yesterday, Jim Cramer of MadMoney called Johnson Controls the "only auto-related company" that he would recommend based on clean and efficient technologies.

More on green investments.