pvl_grounddiffuse

Estimate diffuse irradiance from ground reflections given irradiance, albedo, and surface tilt.

Contents

Syntax

GR = pvl_grounddiffuse(SurfTilt, GHI, Albedo)

Description

Function to determine the portion of irradiance on a tilted surface due to ground reflections. Any of the inputs may be vectors or scalars, as long as all vectors are of the same size.

Inputs

Outputs

Example 1

Calculate the ground reflected diffuse irradiance on an array tilted at 30 degrees from horizontal when GHI = 1,000 W/m^2 and albedo = 0.2.

GR = pvl_grounddiffuse(30, 1000, 0.2)
GR =

   13.3975

Example 2

Calculate the ground reflected diffuse irradiance on an array tilted at 30 degrees from horizontal when GHI = 1,000 W/m^2 and albedo = 0.8 (typical of fresh snow).

GR = pvl_grounddiffuse(30, 1000, 0.8)
GR =

   53.5898

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.

See Also

pvl_perez, pvl_reindl1990, pvl_klucher1979, pvl_haydavies1980, pvl_isotropicsky, pvl_kingdiffuse

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