I would like to install solar panel/cell in my flat office's roof top. Should not difficult to install. Just to install it 2x4, 2x4, 2x4 (total 24 cells, 120cmx80cm wide each cell). Mean, in between 2x4 array with another array, there will be space for maintenance service isle). But between the panel in the array, will be no space (picture 1). It was on my mind. But then there comment saying that there should be space between panel in the array (picture 2), probably just 2-5cm, not so big. In my opinion, the first option is the best while the panel will keep all the energy comes from the solar. But however, I don't know what is the justification for this opinion. Then my question is, what is the best configuration between the two array (option 1 or option 2)?