Current thinking is south facing may not be the best choice... West or south west facing has proven to have advantages... in the morning your energy load is low, as the day passes & the sun moves to the western sky your house heats up & the A/C comes into play, biggest load on your energy demand.... By catching west, southwest sun you extend max solar energy production to match your energy load.... Since what you sent to the grid barely gets compensated & what you use from the grid is billed at full rate you want your used time & production time to match as closely as possible...