Location and Orientation of solar panels

The optimal solar collector (or solar electric modules) orientation isn’t just defined by south or north sun exposure. And location isn't just on the roof.

Solar collectors orientation is also a question of local weather conditions – eventual foggy mornings or cloudy afternoons- and elements that might interfere with sunlight over the solar panels: other buildings, trees, chimneys, etc.

You should study your particular landscape and also your local weather conditions, before determining the orientation of the solar collectors.

Optimal Collector Orientation

Solar collectors should be oriented to maximize the solar energy that they might receive. In most cases the optimal orientation is true south (in the northern hemisphere) or true north (in southern hemisphere countries).

This position shouldn’t however be viewed very strictly: recent investigations prove that collectors can face up to 90º east or west of that position without significant under-performance.

In other words: local weather conditions and landscape particularities (or even aesthetical ones) may justify an orientation different from the true South/North (Northern/Southern hemisphere).

Collectors tilt and their location on the roof

The optimal tilt angle for a solar collector is an angle equal to the latitude of the place where it is located, though most solar collectors have the same tilt as the roof (collectors are mounted flat on the roof). This turns the system much more aesthetical without affecting significantly its performance.

However, a substantial increasing or decreasing of the vertical angle of the collector relatively to the sun may indeed reduce or increase the heat output of the collector. There are reported cases where changing the angle of the collectors causes a significant decreasing of the excessive heat generated in the summer (cases when the systems are oversized; see: Sizing the solar system).

Solar space heating: tilt angle

The tilt angle for solar space heating systems should be higher than those of other systems. Vertical mounted collectors, next to walls, are a good option, in many cases. See: Solar space heating systems.

Location of solar panels

The roof is the more common location for solar panels. But panels have not to be located on the roof. Solar collectors are often located near south facing walls (in northern hemisphere) or north facing walls (in southern hemisphere countries), and most of the swimming pool heating collectors are also located in mounting hardware supplied by the manufacturers.

Roof is just a functional and aesthetic location for solar collectors. The most important is the orientation of the collector and its tilt, which depends mostly on landscape and local weather conditions.