This is one of these great ideas that are so obvious you wonder why no Silicon Valley Solar company has come up with that yet. It takes a 13-year old kid to show how solar cells are positioned the best way.
13-year old Aidan Dwyer won one of the Young Naturalist Award 2011, but that does not give him credit enough for what he actually came up with. Aidan studied how trees grow their leaves. The leaves grow based on the Fibonacci sequence (0,1,1,2,3,5,8,14,21,...). Aidan wanted to know why and the "obvious" answer is that this arrangement collects the most sunlight. Aidan has created a prototype solar tree and found out that arranging solar cells like leaves on a tree yields to 50% more efficiency. Aidan already got his findings already filed as a patent. Expect solar tree forests to replace conventional solar farms in the near future.
Looks like the experiment is flawed. I am not a science expert. So we relied on the fact that Aidan got an award for his work. Either way it is a cool project.