krugman e le energie rinnovabili

I can't understand how growth ,you advocate,  may spring from costly and less available energy. At the end of renewables,  I think, there is a lot of coal and oil at increasing prices.

Just a stupid idea crossed my head: is it possible that you speak for  renewables just for obtain inflation ?
http://krugman.blogs.nytimes.com/2012/07/23/vsps-of-energy/?smid=tw-NytimesKrugman&seid=auto