I made my 180 watts solar panel today.
It produces under 80 watts actually. You need nice sunny day and you have to let sun rays hit directly to panel if you want 100% efficient. I spend 60 dollars to cells. each cell 5 watts. There are 36 cells. Each cells 0.5 volt also. So I made 18 volt solar panel but why?
18 volt required to charge 12 volt battery, however I use my panel to connect grid tie inverter.
I bought 1 kg epoxy for 10 dolars. Encapsulation for 30 dollars. Bandage and other soldering stuff for 10 dollars. It is nearly 100 dollars and a lot of time with low cost metarial. If I bought 150 watts better quality encapsulation panel It would cost 120 dollars.
So it is better to but I think.
