In contrast a north southern hemisphere facing roof gets sunshine from dawn to dusk.
Solar panels on east and west facing roofs.
Therefore directions like southwest or southeast are fine.
For homes with roofs that face to the south and that have an appropriate pitch for mounting solar panels installing an efficient home solar system is fairly straight forward because both the roof orientation and angle pitch are optimal for harvesting clean energy from the sun.
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.
However under the right circumstances it is possible to have an east west split of solar panels on a single inverter input like the diagram above imagine the left hand 3 panels facing west and the right hand 3 panels facing east and still have almost the same performance as if they were on separate strings attached to a two seperate inverter inputs.
Technically east facing panels can get as much sun as west facing ones as long as there are no other issues like morning fog or clouds or shade.
Of course you cannot install east west facing solar panels on your roof if it does not already slant in those directions.
If you went with a professional solar installer they probably had a good reason to install panels facing east rather than west.
In winter when the sun is at an angle less than the pitch of the roof the panels will receive no sunlight.
With east or west facing panels the sun will be behind the roof for half the day.
If you look back to systems that were built a few years ago you would typically find them facing south says david wedepohl director of communications and markets at the german solar industry association bsw.