Use winter sunshine hours instead of summer hours whenever you are calculating how many solar panels you will need. This is because winter sunshine hours only add up to about half that of summer. It is better to overestimate how many panels you will need rather than underestimate. If you underestimate, you will end up losing power when you need it.
How dense your solar panels are will determine their efficiency. Getting high density solar panels may cost you quite a bit, but after a while they'll pay for themselves because they produce more power. Before you select your solar panels, you should consider panel density.
I designed my system primarily as a backup system in case the grid goes down long term. I just happen to run it every day, weather permitting, to help lower my …
Keep your solar panels out of the shade. It might seem obvious, but your solar panels do need sun. Make sure that you are not installing them in the shade. Trim back the branches on surrounding trees if you need to. Failing to do so could cost you more than half your energy output.