GM General Chairman and CEO Dan Akerson raised a few eyebrows in the fuel cell industy with his recent statements voicing concern over the feasibility of hydrogen-fueled cars. It was a mere nine years ago that General Motors predicted thousands of hydrogen fuel cell cars would take the road by next year.

Why the change of heart? Though Akerson notes that great strides have been made in the affordability of fuel cell technology, he doesn't see the vehicles becoming cost efective till at least 2020, and likely beyond.