I'm optimistic the combined energy of research,technology, discussion, political action that are occuring we will get some positive results in obtaining new sources of energy and reduce global warming.
I am optomistic about this due to;
1) Large amount of individuals, university research labs, entreprenuers and companies that are working on this problem. Market forces help driving this.
2) In general, the world and the US do recognize this as an important issue
3) There are a number of technologies that are now new or are improved:
a) massive computing resources allow us to do modeling
b) better understanding allowing us to do biomimicing of breaking down materials to fuel, creating photosynthesism, reducing wind drag in transportation
d) improvements in battery technology
To see what the scientists and thought leaders of the Edge collaborative website are optomistic about click on the picture at the top of the page.