They're not in production yet, so they haven't been proven. Doing calculations on paper doesn't mean you can actually do it at the end of the day.

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Micro fuel cells are years away from commercial deployment, but considerable R&D is underway funded in part by the military to power portable communications equipment in the field.

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The solar shortage will be most pronounced in 2006, and we anticipate only modest solar industry production growth of 9 percent.

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