Let me apologize for going on about this, but I think that the efforts currently underway among the automobile manufacturers are among the most important things occurring at the moment in ecology/environmentalism/sustainable futures movement, and yet they may be otherwise be somewhat off of most ecologists' radar screens.
For example, today's images from C|Net are worth considering. The first URL is a set of slides regarding Chevrolet's introduction today of their new plug-in, hydrogen fuel cell car, the Volt: http://news.com.com/2300-11389_3-6177935.html The earlier version of the car, which was introduced only in January, was a short-range battery electric version. The second set of slides is a little more whimsical. They show a set of toys that produce their own hydrogen by electrolysis and combust it in fuel cells. http://news.com.com/2300-11392_3-6177768-1.html That indeed may be the future. Hydrogen can be produced anywhere, by anyone, and one possible future may be that people will produce their own fuel locally, at their home, photovoltaically. Given that the only real "fuels" in this process are sunlight and water, such a process would seem to be the ultimate in a sustainable future with the absolute smallest environmental footprint. There are clearly economies of scale to be had with any process, so local production may not ultimately make good economic sense, but it is nonetheless possible, which is an altogether different proposition than individuals refining their own gasoline or ethanol on site. Fuel cells have sufficient promise, and are so scalable, that it is well within reason that your laptop will be powered by one instead of the current lithium-ion batteries in a few years or so. If so, these "batteries" will possess a usable lifetime between "charges" of days instead of hours. They're already being produced for military applications: http://www.ultracellpower.com/assets/pdf/Ultracell_General_data.pdf although these particular fuel cells run off of methanol rather than hydrogen directly. Wirt Atmar
