Tilt angle - PV array

The tilt angle of the photovoltaic (PV) array is the key to an optimum energy yield. Solar panels or PV arrays are most efficient, when they are perpendicular to the sun's rays.

The default value is a tilt angle equal to the station's latitude plus 15 degrees in winter, or minus 15 degrees in summer (1). This normally maximizes annual energy production. 

However, through out the year the sun's path and the solar altitue vary.  In europe for example the solar altitute during summer reaches 60°-65° whereas in winter solar angles are as low as 13° - 18°.

To optimize capture of solar panels a tilt angle of 28° - 30° is recommended. However, tilt angles between 20° - 60° are possible without great yield losses. Increasing the tilt angle favors energy production in the winter, while decreasing the tilt angle favors energy production in the summer.

Find out the sun path and solar altitude for your U.S. location. 

Click here » Sun path 

• Orientation