fCompI: Calculation of solar irradiance on a horizontal surface
In oscarperpinan/solar: Radiation and Photovoltaic Systems

Description Usage Arguments Value Author(s) References See Also Examples

From the daily global, diffuse and direct irradiation values supplied by fCompD, the profile of the global, diffuse and direct irradiance is calculated with the rd and rg components of fSolI.

1	fCompI(sol, compD, G0I, corr = 'none', f, filterG0 = TRUE)

`sol`	A `Sol` object as provided by `calcSol` or a `zoo` object as provided by `fSolI`.
`compD`	A `zoo` object as provided by fCompD. It is not considered if `G0I` is provided.
`G0I`	A `Meteo` object from `readBDi`, `dfI2Meteo` or `zoo2Meteo`, or a `zoo` object containing intradaily global irradiation (Wh/m²) on a horizontal surface. See below for `corr = 'none'`.
`corr`	A character, the correlation between the the fraction of intradaily diffuse irradiation and the clearness index to be used. It is ignored if `G0I` is not provided. With this version several correlations are available, as described in `corrFdKt`. You should choose one of intradaily proposals. For example, the `FdKtCLIMEDh` is selected with `corr = 'CLIMEDh'`. If `corr = 'user'` the use of a correlation defined by a function `f` is possible. If `corr = 'none'` the `G0I` object must include information about global, diffuse and direct intradaily irradiation with columns named `G0`, `D0` and `B0`, respectively.
`f`	A function defininig a correlation between the fraction of diffuse irradiation and the clearness index. It is only neccessary when `corr = 'user'`
`filterG0`	A logical. If `TRUE` (default) this function sets the global irradiation values to `NA` when they are higher than the extra-atmospheric irradiation values.

A zoo with these components:

`kt`	numeric, clearness index.
`fd`	numeric, diffuse fraction.
`G0`	numeric, global irradiance on a horizontal surface, (W/m²)
`D0`	numeric, diffuse irradiance on a horizontal surface, (W/m²)
`B0`	numeric, direct irradiance on a horizontal surface, (W/m²)

Oscar Perpiñán Lamigueiro.

Collares-Pereira, M. y Rabl, A., The average distribution of solar radiation: correlations between diffuse and hemispherical and between daily and hourly insolation values. Solar Energy, 22:155–164, 1979.
Perpiñán, O, Energía Solar Fotovoltaica, 2015. (https://oscarperpinan.github.io/esf/)
Perpiñán, O. (2012), "solaR: Solar Radiation and Photovoltaic Systems with R", Journal of Statistical Software, 50(9), 1-32, doi: 10.18637/jss.v050.i09

fCompD, fSolI, calcSol, corrFdKt.

lat <- 37.2

BTd <- fBTd(mode = 'serie')
solD <- fSolD(lat, BTd[100])
solI <- fSolI(solD, sample = 'hour')
G0d <- zoo(5000, index(solD))
compD <- fCompD(solD, G0d, corr = "Page")
fCompI(solI, compD)

sol <- calcSol(lat, fBTd(mode = 'prom'), sample = 'hour', keep.night = FALSE)

G0dm <- c(2.766, 3.491, 4.494, 5.912, 6.989, 7.742,
          7.919, 7.027, 5.369, 3.562, 2.814, 2.179)*1000

Ta <- c(10, 14.1, 15.6, 17.2, 19.3, 21.2, 28.4, 29.9,
        24.3, 18.2, 17.2, 15.2)

BD <- readG0dm(G0dm = G0dm, Ta = Ta, lat = lat)
compD <- fCompD(sol, BD, corr = 'Page')
compI <- fCompI(sol, compD)
head(compI)

## Use of 'corr'.  The help page of calcG0 includes additional examples
## with intradaily data xyplot(fd ~ kt, data = compI)

climed <- fCompI(sol, G0I = compI, corr = 'CLIMEDh')
xyplot(fd ~ kt, data = climed)

ekdh <- fCompI(sol, G0I = compI, corr = 'EKDh')
xyplot(fd ~ kt, data = ekdh)

brl <- fCompI(sol, G0I = compI, corr = 'BRL')
xyplot(fd ~ kt, data = brl)