pvl_isotropicsky

Determine sky diffuse irradiance on a tilted surface using the isotropic sky model.

Contents

Syntax

SkyDiffuse = pvl_isotropicsky(SurfTilt, DHI)

Description

The isotropic sky model [1], [2] regards the sky as a uniform source of diffuse irradiance. Thus the sky diffuse irradiance on a tilted surface can be found from the diffuse horizontal irradiance and the tilt angle of the surface.

Inputs

Outputs

Example

Calculate sky diffuse on a 30 deg tilted array when diffuse horizontal irradiance equals 200 W/m^2.

SkyDiffuse = pvl_isotropicsky(30, 200)
SkyDiffuse =

  186.6025

References

[1] Loutzenhiser P.G. et. al., 2007. Empirical validation of models to compute solar irradiance on inclined surfaces for building energy simulation, Solar Energy vol. 81. pp. 254-267.

[2] Hottel, H.C., Woertz, B.B., 1942. Evaluation of flat-plate solar heat collector. Trans. ASME 64, 91.

See Also

pvl_perez, pvl_reindl1990, pvl_klucher1979, pvl_haydavies1980, pvl_grounddiffuse, pvl_kingdiffuse

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