Fuel cells interest me more than batteries because I'm not convinced that the materials needed for batteries are renewable. (Yes, I've already heard people argu

Fuel cells interest me more than batteries because I'm not convinced that the materials needed for batteries are renewable. (Yes, I've already heard people argue that future battery technologies may not have this problem. I'd be more convinced by indications of how this problem might be solved than simple assertions that it will be solved.) I think diesel will have its niche in the future, as the energy density concerns are legitimate and important for many applications. Biodiesel also doesn't have the same limitations in terms of materials the batteries do. For personal transportation, I'm a strong proponent of human power, particularly walking and biking. No new magic technology is needed as far as I'm concerned. This is not practical in many places in the US, but if someone were to spend as much effort selecting where they live to have a good cycling commute as they do when selecting where they live to have a good driving commute, the problem would be mostly solved. Many people would have to change their lifestyles to do this, but I think those who do would typically find the changes acceptable or an improvement over their current situation.