pvl_kingdiffuse
Determine the total diffuse irradiance on a tilted surface using the King model.
Contents
Syntax
POADiffuse = pvl_kingdiffuse(SurfTilt, DHI, GHI, SunZen)
Description
This model (developed by David L. King at Sandia National Laboratories) determines the total diffuse irradiance (sky diffuse and ground reflected irradiance) on a tilted surface using the surface tilt angle, diffuse horizontal irradiance, global horizontal irradiance, and sun zenith angle. The model combines the isotropic sky diffuse model with an empirical formula for the albedo for the ground-reflected irradiance.
Inputs
- SurfTilt - a scalar or vector of surface tilt angles in decimal degrees. If SurfTilt is a vector it must be of the same size as all other vector inputs. SurfTilt must be >=0 and <=180. The tilt angle is defined as degrees from horizontal (e.g. surface facing up = 0, surface facing horizon = 90).
- DHI - a scalar or vector of diffuse horizontal irradiance in W/m^2. If DHI is a vector it must be of the same size as all other vector inputs. DHI must be >=0.
- GHI - a scalar or vector of global horizontal irradiance in W/m^2. If GHI is a vector it must be of the same size as all other vector inputs. GHI must be >=0.
- SunZen - a scalar or vector of apparent (refraction-corrected) zenith angles in decimal degrees. If SunZen is a vector it must be of the same size as all other vector inputs. SunZen must be >=0 and <=180.
Outputs
- POADiffuse - the total diffuse irradiance on a tilted surface.
Example
SurfTilt = 30; SurfAz = 180; DHI = 47; GHI = 473; SunZen = 60; POADiffuse = pvl_kingdiffuse(SurfTilt, DHI, GHI, SunZen)
POADiffuse = 65.3974
References
[1] Lave, M., Hayes, W., Pohl, A., Hansen, C., 2015. Evaluation of Global Horizontal Irradiance to Plane-of-Array Irradiance Models at Locations Across the United States, J. of Photovoltaics v5(2), pp. 597-606.
See Also
pvl_perez, pvl_reindl1990, pvl_klucher1979, pvl_haydavies1980, pvl_grounddiffuse, pvl_ephemeris
Copyright 2014 Sandia National Laboratories