pvl_reindl1990
Determine sky diffuse irradiance on a tilted surface using Reindl's 1990 model.
Contents
Syntax
SkyDiffuse = pvl_reindl1990(SurfTilt, SurfAz, DHI, DNI, GHI, HExtra, SunZen, SunAz)
Description
Reindl's 1990 model ([1] equation 8, [2]) estimates the sky diffuse irradiance on a tilted surface using the surface tilt angle, surface azimuth angle, diffuse horizontal irradiance, direct normal irradiance, global horizontal irradiance, extraterrestrial irradiance, sun zenith angle, and sun azimuth angle.
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)
- SurfAz - a scalar or vector of surface azimuth angles in decimal degrees. If SurfAz is a vector it must be of the same size as all other vector inputs. SurfAz must be >=0 and <=360. The azimuth convention is defined as degrees east of north (e.g. North = 0, East = 90, West = 270).
- 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.
- DNI - a scalar or vector of direct normal irradiance in W/m^2. If DNI is a vector it must be of the same size as all other vector inputs. DNI 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.
- HExtra - a scalar or vector of extraterrestrial normal irradiance in W/m^2. If HExtra is a vector it must be of the same size as all other vector inputs. HExtra 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.
- SunAz - a scalar or vector of sun azimuth angles in decimal degrees. If SunAz is a vector it must be of the same size as all other vector inputs. SunAz must be >=0 and <=360. The azimuth convention is defined as degrees east of north (e.g. North = 0, East = 90, West = 270).
Output
- SkyDiffuse - the sky diffuse irradiance on a tilted surface in W/m^2. SkyDiffuse is a column vector vector with a number of elements equal to the input vector(s).
Example
SurfTilt = 30; SurfAz = 180; DHI = 47; DNI = 969; GHI = 473; HExtra = pvl_extraradiation(60); SunZen = 60; SunAz = 161; SkyDiffuse = pvl_reindl1990(SurfTilt, SurfAz, DHI, DNI, GHI, HExtra,SunZen, SunAz)
SkyDiffuse = 68.6801
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] Reindl, D.T., Beckmann, W.A., Duffie, J.A., 1990. Evaluation of hourly tilted surface radiation models. Solar Energy 45 (1), 9–17.
See Also
pvl_perez, pvl_grounddiffuse, pvl_klucher1979, pvl_haydavies1980, pvl_isotropicsky, pvl_kingdiffuse, pvl_extraradiation
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