This is an incredibly lazy blog article. The author hasn't even attempted to do any calculations he's just contemplating someone else doing them.

I don't think he has thought the problem through or researched it at all. Reading the wiki article ( http://en.wikipedia.org/wiki/Photovoltaic_power_station#Sola... ) shows that people already make the calculations of whether to pay for sun tracking which gets you an extra 30% energy. Obviously at some point the tracking mechanism will cost more than 30% of the energy produced. That's the cut off. And at that point the arrays installed will be fixed non tracking arrays tilted towards the equator at an angle calculated to get the maximum energy during the year.