The issue, at least on the surface, is “bankability,” i.e., maturity of the technology, along with the obvious fact that the price of PV is falling sharply – 30% in 2010 alone. But at a certain point, I’m hoping that someone somewhere sees the awesome potential of CSP and really starts to crank on it.
When that happens, we’ll start to see ideas like Ahura Energy start to come into greater focus, if you’ll pardon the pun.
Solar thermal, of course, comes in many different flavors — some (like Ahura) claiming to have made breakthroughs in cost and/or efficiency. I’ve met with these people, like the concept as I understand it, but still haven’t been told the details of the secret sauce.