Terrain Tilt and Azimuth

Terrain Tilt and Azimuth

PV plant specification parameters for non-horizontal terrain

For solar farm facilities on an inclined surface, you need to gather information about terrain tilt and terrain azimuth.

Solar farm facilities are often placed on terrain which is not perfectly horizontal. For this purpose, the PV modelling tools in our Rooftop PV Model allows you to provide information about the aspect of the terrain your facility is installed upon.


The image above is an extreme example of a non-horizontal terrain.

Two data paramaters which can be used for non-horizontal terrain

Terrain Tilt

It is measured in degrees, and is the measurements of decline of the Earth's surface from horizontal. In other words, a site with a perfectly flat/horizontal surface will have a terrain slope value of zero. The value provided should be the *average* of terrain slope at the site, measured in the downhill direction with a positive value in degrees. Read more about Terrain Tilt in this article.

Terrain Azimuth

It is also measured in degrees. It represents the compass direction the sloping terrain surface is pointed. The coordinate system follows the standards in the rest of our API products: South is -180, East is -90, North is 0 & West is 90. The value provided should be the average value of azimuth for the Earth's surface beneath your solar farm facility. Read more about Terrain Azimuth in this article.