Why South Facing Roof Get More Sun

A north facing home gets sun at the back of the house and is typically darker and naturally cooler than a south facing one.

Why south facing roof get more sun.

Then use a flashlight to represent the sun and rotate the globe. In general solar panels that are oriented directly east or directly west will produce about 20 percent less electricity than if they were facing south. If the building s axis is located on the east west direction with its longest dimension facing the south more of the building is situated to. Even with this decrease in performance solar panels will produce enough electricity to save you hundreds of dollars a year.

Near the equator north and south facing slopes receive roughly the same amount of sunlight because the sun is almost directly overhead. Because the sun rises in the east and sets in the west the side of the building that is utilized for solar gain needs to be facing the south to take maximum advantage of the sun s potential energy. A good way to visualize this is to get a globe and tape a monopoly house or sugar cube to it to represent your house. Try both summer and winter orientations for the axis.

This change in the sun s apparent angle between summer and winter is why that works. At the poles north and south slopes tend to be either shrouded in darkness all winter long or bathed in sunlight all summer long with only slight variation between the slopes in spring and fall. Why orientation matters with rooftop solar.