Panels mounted on a standard pitch roof facing east or west will produce approximately 15 less output than panels mounted on a south facing roof of a standard pitch.
Installing solar panels on north facing roof.
The panels are installed on a north facing roof with a pitch that looks like about 9 12 37 angle up from the ground.
An ideal south facing roof here is pitched at 7 12 39ish degrees and the north side of that roof will produce less than half as much electricity.
However the economics of installing solar panels on a roof that does not face the south still usually stack up for the homeowner.
While it is technically possible to install solar panels on the north side of your roof they need to be mounted so that they oppose the roof s slant in order to generate electricity.
There are long runs of external conduit that join strings together which is a big problem in its own right.
Generally this isn t the best solution since these panels still won t yield much energy.
Adding modules on the north side of the roof will not add much bang for the customer s solar buck and would qualify as solar malpractice in my book.