There are two methods for calculating the tilt angle for solar panels.
Best azimuth for solar panels.
Positive 90 degrees is facing due west negative 90 degrees is facing due east.
In most of the solar pv energy calculator tools an azimuth value of zero is facing the equator in both northern and southern hemispheres.
Both of these angles require latitude degrees.
The compass angle shows 180 for south 90 for east and 270 for west.
Since solar panels are more productive when the sun s rays are perpendicular to their surfaces the certainly best orientation is the one directly true south azimuth angle 180.
But that of course isn t always possible and further with today s improved panels a roof facing east southeast southwest or west also work very well.
On the contrary in the countries of the southern hemisphere such as south africa and australia the best orientation is true north.
Azimuth is the array s east west orientation in degrees.
For example the azimuth is 90 if solar is in the due east it is 90 if solar is in due west.
For best results your solar panels should face toward the equator.
The decision of azimuth.
The tilt is 0 if solar panel parallel to horizon to design the tilt is 90 if the solar panel is vertical to design.
The azimuth has decided the incidence direction of sunlight decided the lighting conditions of solar from various different orientation hillsides or buildings.
If you live in the northern hemisphere face them south.
Similarly you can calculate the angle for winter by adding 15.
Generally it s common knowledge in the solar industry that these south facing panels should be tilted between a 30 and 40 degree angle.
This being the case the general best practice to date has always been to position solar panels facing south in order to capture the maximum amount of sunlight overall.
Whatever your latitude is you can subtract 15 from it to calculate the angle for summer.
The tilt is included angle of horizon and solar panel.