Clear-sky

Helios.clearsky_haurwitz — Method

clearsky_haurwitz(solpos::SolarPosition)

Implements the Haurwitz clear sky model for global horizontal irradiance (GHI) as presented in [29, 30].

A report on clear sky models found the Haurwitz model to have the best performance in terms of average monthly error among models which require only the Sun's elevation [31].

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Helios.clearsky_ineichen — Method

clearsky_ineichen(
    location::Location,
    datetime::DateTime;
    solpos::SolarPosition,
    relative_airmass,
    linke_turbidity,
    extraterrestial_radiation,
    perez_enhancement=false,
)

Returns the global horizontal irradiance (GHI), direct normal irradiance (DNI), and diffuse horizontal (DHI), all in [W/m^2], following the Ineichen/Perez clear sky model [32, 33].

Keywords

solpos: Solar position. Defaults to spa(location, datetime).
relative_airmass: Relative airmass. Defaults to relative_airmass_kastenyoung1989.
linke_turbidity: Linke turbidity factor. Defaults to linke_turbidity_meteotest.
extraterrestrial_radiation: Extraterrestrial irradiance. Defaults to extraterrestrial_irradiance_spencer1971.
perez_enhancement::Bool=false: Whether to apply the Perez enhancement factor.

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Helios.clearsky_simplified_solis — Method

clearsky_simplified_solis(
    location::Location,
    solpos::SolarPosition;
    extraterrestial_radiation,
    aod700=0.1,
    precipitable_water=1.0
)

Calculate the clear sky direct normal irradiance (DNI), and diffuse horizontal irradiance (DHI) according to the simplified Solis model.

Reference [34] describes the accuracy of the model as being 15, 20, and 18 W/m^2 for the beam, global, and diffuse components, respectively. Reference [35] provides comparisons with other clear sky models.

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