pvl_getaoi

Determine solar angle of incidence on a tilted surface.

Contents

Syntax

AOI = pvl_getaoi(SurfTilt, SurfAz, SunZen, SunAz)

Description

Determines the angle of incidence in degrees between a surface normal and a vector pointed at the sun. The surface is defined by its tilt angle from horizontal and its azimuth pointing angle. The sun position is defined by the apparent (refraction corrected) sun zenith angle and the sun azimuth angle.

Inputs

Outputs

Example 1

Sun at zenith

SurfTilt = 30;
SurfAz = 180;
SunZen = 0;
SunAz = 180;
AOI = pvl_getaoi(SurfTilt, SurfAz, SunZen, SunAz)
AOI =

   30.0000

Example 2

Sun low in southwestern sky

SurfTilt = 30;
SurfAz = 180;
SunZen = 30;
SunAz = 225;
AOI = pvl_getaoi(SurfTilt, SurfAz, SunZen, SunAz)
AOI =

   22.0622

References

[1] D.L. King, J.A. Kratochvil, W.E. Boyson , 1997. Spectral and Angle-of-Incidence Effects on Photovoltaic Modules and Solar Irradiance Sensors. 26th IEEE Photovoltaic Specialists Conference.

See Also

pvl_ephemeris

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