Last week David Goodstein from Cal Tech came to Rice and gave a great lecture based on his book, Out of Gas, about the "end of the age of oil". The lecture was so distressing that I'm still thinking about it quite a bit almost two weeks later. Goodstein's main point is that our ever growing energy needs, coupled with the rising demand from the rest of the world (read: China and India, who for some wacky reason would like to enjoy standards of living similar to ours), make it highly highly likely that we will run out of fossil fuels sometime this century. Indeed, his one prediction is that "Civilization as we know it will end in the next 100 years, as we run out of fuel."
I know, I know - there are lots of "peak oil" nutjobs out there, but Goodstein isn't one of them. He's just a very bright guy who makes a really convincing case.
What are our options, according to him? Basically fusion (which is and might always be about 40 years away), or solar. Fission runs into trouble from problems of capacity (to satisfy 10 TW of demand will require building typical 1 GW reactors at a rate of one per day for 30 years), let along issues of fuel reprocessing.
Frankly I think the time is right for an Apollo/Manhattan Project style investment in this problem. Dumping less than 1% of the GDP ($100B, or, in better units, a few months in Iraq, or 1/3 of the annual service on the federal debt) into this per year at one or two re-dedicated national labs makes a lot of sense to me. It's much easier to invest now than when things get really desparate....