An interesting article by Ronald Cooke entitled, "Alternative Energy: It's Time to Evaluate Our Options".
In this article, Cooke examines our energy options as we come to the end of an era of "cheap oil". He divides the energy universe into two basic application groups, mobile fuels and stationary fuels, and goes on to evaluate possible energy sources according to risk profile, reliability of supply chain and economics.
Cooke makes some very interesting arguments, and I found his comments on energy subsidies especially worthwhile. Check it out, at the link listed above.