Robert,

To be fair, though things are not happening as fast as Kurzweil said and as you pointed out energy is his blind spot, we are now for the first time in history able to build infrastructure that is capable of powering our civilization from renewables.

That we haven't done so (yet) and that since the members of our civilization are not all rowing in the same direction we may not is a different question.

Also: OK so he does look 60 (though I'd have said more like 50) he looks like he's in great shape for his age. Looking at the office where I'm currently working, there are plenty of people in their late 40s in worse shape than Ray.

we are now for the first time in history able to build infrastructure that is capable of powering our civilization from renewables.

That we haven't done so (yet) and that since the members of our civilization are not all rowing in the same direction we may not is a different question.

It's no more a different question than the "above-ground" factors are a different question from the geology. We won't do it because we are not capable as a species. It will, however, indeed happen - that "we" power civilization from renewables. Whatever civilization it is, though, it won't be "ours" and "we" will be a different fork of the ape tree. The other side of this singularity we will become a different species.

I'm concerned that even that expresses too much unfounded hope.

cfm in Gray, ME, parking cars at the End of the Universe.