Except you don't, you just see limited installations here and there.
If solar power has such a quick payback period why aren't more investment groups funding it?
Are the panels not available in sufficient quantity?
Global installations for 2016 are also on track to set a new record, surpassing 2015 installations by 48%: https://cleantechnica.com/2016/11/30/global-solar-installati...
And despite these records, the manufacturing side of the industry is currently demand-constrained rather than supply-constrained.
When you say you there's just "limited installations here and there," are you estimating from whatever you personally see in your local area?
Also, global solar is going up like crazy. Global sustained growth rate of around 40% is crazy fast. If that keeps on for a bit more than ten years, 100% of current global electricity demand is covered by solar. Just for comparison, there exists no two subsequent full years of iPhone production where Apple would have managed to achieve 100% growth.
I think his numbers didn't take into consideration the expensive backup power plant that you have to have ready even if you have adequate solar capacity.