Since the sun rises in the east and sets in the west, solar panels do best when they face south. South-facing solar panels always face the sun, which means they never have a shadow cast on them.
The direction that the panels face isn’t the only thing to be considered when deciding where to place them. There are many factors that should be considered when deciding where to place the panels.
The Part Roof, Pitch and Shade Play in Solar Panel Orientation
The pitch of a home (or angle of the roof) definitely plays a part in solar panel orientation. Homes with steep or flat roofs require special equipment, making it more expensive and harder to install. So yes-having a boring roof actually has a financial benefit!
Effect of Tilt Angle on Solar Panel Output
The perfect roof pitch for solar panels equals the latitude of the location of the installation. However, if this angle isn’t possible, pitch angles between 30 and 45 degrees will work. Having solar panels at the perfect angle increases the production of the solar array. For this reason, flat-roofed homes are ideal.
Flat Roofs and Ballasted Solar Panels
Homes with flat roofs need different mounting systems. Ballasted mounts add flexibility for solar panel tilt, holding solar panels in place on flat roofs. These mounts have racking set at the perfect angle for the latitude of the home.
The Best Direction for Solar Panels To Face
Although south-facing solar modules provide the best results, east and west-facing solar panels also produce a sizable amount of energy. Since objects facing the north have more shade, solar panel placement should never go on the north side of a roof.
The Effect of Shade on Solar Panels
Solar panels need as much sun as possible. Objects like chimneys, trees, and adjacent buildings casting a shadow over the ideal locations for installation make the installation more difficult.
Best Roof Shape for Solar Panels
The shape of a house plays a significant role in whether solar will work. The ideal shape of a home for residential solar includes a roof with large amounts of space facing east, west, or south.
Available Space Matters
An average residential solar panel measures 65 by 39 inches, which equals approximately 17.5 square feet for one solar panel. An average roof has about 3,000 square feet of space. If nothing shades the home, all the pitches meet solar panel tolerances, and no portion of the roof faces north, a typical roof could hold up to 171 solar panels. However, at least one of these factors often takes place, reducing the solar potential of the rooftop.
Best Roof Style for Solar Panels
Many roofing styles exist out there, and the pitch and direction of the home don’t comprise everything that goes into a roof’s solar viability. Different types of shingles can also make installing solar difficult. Some roofs have very steep pitches, making it hard to install solar panels. Other homes face south, meaning solar panels function best on the front.
Common Roof Types for Solar Installations
Common rooftop shingles include asphalt, tile, wood, shake, slate, composite, rubber, copper, and metal. Some options, like shake and wood, require extra care, but it’s possible. Given the difficulties associated with installing on different roof types, some companies will not install solar panels on certain roofs.
If the shingles need replacing, waiting until the roof gets replaced will cost less. Homes that don’t have a roof yet or need re-shingling often make good candidates for in-roof solar installations.