I have 11 panels (size 120x300 cm) on my roof connected in one big parallel group. I just got 5 more. The question is how to connect them for best performance (I live in Denmark so I need to get the most out of them). You can see a picture here:


I read somewhere that it is better to divide a large number of panels into groups. But should the groups be connected in parallel or serial? Or combined? My friend (who knows a lot about pools and solar heating) suggested this setup:


I thought 3 or 4 groups in parallel were better but my friend pointed out that it would be the same as one big group in parallel.

Any ideas are most welcome