Cost-Effective Solar Thermal

My colleague Gary Tulie wrote a great comment on my recent post on solar thermal,  in which he explains the opportunities for improvement in efficiencies for these technologies.  Here’s something I would add:

I’m betting against tower CSP (shown here) as a long-term scalable approach, as the mirrors located at various distances from the tower need to be fabricated in different shapes, and the tracking mechanisms, of which there are thousands, need to be extremely precise.  All this represents huge complexity and cost. Abengoa, the world leader in CSP, which I mentioned in my post, relies on a proprietary design in parabolic trough, which is far simpler. The challenge, of course, is temperature;  for the reason Gary mentioned,  i.e., the Carnot limit,  high temperatures are required for decent efficiencies.