Natural-gas vehicles are a tough sell. Sure, natural gas is considerably cheaper than gasoline, but natural-gas refueling stations are few and far between.

What we really need is a vehicle capable of running on both gasoline and natural gas. A natural gas/gasoline hybrid would let us fill up with gasoline on our daily commute to work and natural gas when we hit the freeway for a road trip.

As it turns out, such a vehicle will soon be available.

The bi-fuel fix
Clean Energy Fuels (Nasdaq: CLNE) is working on constructing a network of natural-gas stations along some of the nation's major highways. Meanwhile, General Motors (NYSE: GM) is working with Fuel Systems Solutions (Nasdaq: FSYS) to bring to market a natural-gas bi-fuel pickup, which is to be released sometime late next year.

Not to be outdone, Ford (NYSE: F) is teaming up with Westport Innovations (Nasdaq: WPRT) on a bi-fuel truck as well.

The bad news is the bi-fuel trucks will initially be available only for commercial customers, but if they prove to be a success, I suspect we could see a similar offering available to the public.

The bottom line
Bi-fuel vehicles could be the future, as they offer an obvious solution to the infrastructure dilemma. The companies supplying the major auto manufacturers with the bi-fuel technology could experience massive growth if this trend takes hold.