calcGef: Irradiation and irradiance on the generator plane.
In oscarperpinan/solar: Radiation and Photovoltaic Systems

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

This function obtains the global, diffuse and direct irradiation and irradiance on the generator plane from the values of daily or intradaily global irradiation on the horizontal plane. It makes use of the functions calcG0, fTheta, fInclin. Besides, it can calculate the shadows effect with the calcShd function.

calcGef(lat,
        modeTrk = 'fixed',
        modeRad = 'prom',
        dataRad,
        sample = 'hour',
        keep.night = TRUE,
        sunGeometry = 'michalsky',
        corr, f,
        betaLim = 90, beta = abs(lat)-10, alfa = 0,
        iS = 2, alb = 0.2, horizBright = TRUE, HCPV = FALSE,
        modeShd = '',
        struct = list(),
        distances = data.frame(),
        ...)

`lat`	numeric, latitude (degrees) of the point of the Earth where calculations are needed. It is positive for locations above the Equator.
`modeTrk`	character, to be chosen from `'fixed'`, `'two'` or `'horiz'`. When `modeTrk = 'fixed'` the surface is fixed (inclination and azimuth angles are constant). The performance of a two-axis tracker is calculated with `modeTrk = 'two'`, and `modeTrk = 'horiz'` is the option for an horizontal N-S tracker. Its default value is `modeTrk = 'fixed'`
`modeRad, dataRad`	Information about the source data of the global irradiation. See `calcG0` for details.
`sample, keep.night`	See `calcSol` for details.
`sunGeometry`	`character`, method for the sun geometry calculations. See `calcSol`, `fSolD` and `fSolI`.
`corr, f`	See `calcG0` for details.
`beta`	numeric, inclination angle of the surface (degrees). It is only needed when `modeTrk = 'fixed'`.
`betaLim`	numeric, maximum value of the inclination angle for a tracking surface. Its default value is 90 (no limitation))
`alfa`	numeric, azimuth angle of the surface (degrees). It is measured from the south (`alfa = 0`), and it is negative to the east and positive to the west. It is only needed when `modeTrk = 'fixed'`. Its default value is `alfa = 0`
`iS`	integer, degree of dirtiness. Its value must be included in the set (1,2,3,4). `iS = 1` corresponds to a clean surface while `iS = 4` is the selection for a dirty surface. Its default value is 2.
`alb`	numeric, albedo reflection coefficient. Its default value is 0.2
`modeShd, struct, distances`	See `calcShd` for details.
`horizBright`	logical, if TRUE, the horizon brightness correction proposed by Reind et al. is used.
`HCPV`	logical, if TRUE the diffuse and albedo components of the effective irradiance are set to zero. HCPV is the acronym of High Concentration PV system.
`...`	Additional arguments for `calcSol` and `calcG0`

A Gef object.

Oscar Perpiñán Lamigueiro.

Hay, J. E. and McKay, D. C.: Estimating Solar Irradiance on Inclined Surfaces: A Review and Assessment of Methodologies. Int. J. Solar Energy, (3):pp. 203, 1985.
Martin, N. and Ruiz, J.M.: Calculation of the PV modules angular losses under field conditions by means of an analytical model. Solar Energy Materials & Solar Cells, 70:25–38, 2001.
D. T. Reindl and W. A. Beckman and J. A. Duffie: Evaluation of hourly tilted surface radiation models, Solar Energy, 45:9-17, 1990.
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

calcG0, fTheta, fInclin, calcShd.

lat <- 37.2

###12 Average days.

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)

##Fixed surface, default values of inclination and azimuth.

gef <- calcGef(lat = lat, modeRad = 'prom', dataRad = list(G0dm = G0dm, Ta = Ta))
print(gef)
xyplot(gef)

##Two-axis surface, no limitation angle.

gef2 <- calcGef(lat = lat, modeRad = 'prom',
                dataRad = list(G0dm = G0dm, Ta = Ta),
                modeTrk = 'two')
print(gef2)
xyplot(gef2)

struct = list(W = 23.11, L = 9.8, Nrow = 2, Ncol = 8)
distances = data.frame(Lew = 40, Lns = 30, H = 0)

gefShd <- calcGef(lat = lat, modeRad = 'prom',
                  dataRad = list(G0dm = G0dm, Ta = Ta),
                  modeTrk = 'two',
                  modeShd = c('area', 'prom'), 
                  struct = struct, distances = distances)
print(gefShd)

## Not run: 
##Fixed surface using Aguiar method
gefAguiar <- calcGef(lat = lat, modeRad = 'aguiar', dataRad = G0dm)

##Two-axis tracker, using the previous result.
##'gefAguiar' is internally coerced to a 'G0' object.

gefAguiar2 <- calcGef(lat = lat, modeRad = 'prev', dataRad = gefAguiar, modeTrk = 'two')
print(gefAguiar2)
xyplot(gefAguiar2)

###Shadows between two-axis trackers, again using the gefAguiar result.

struct = list(W = 23.11, L = 9.8, Nrow = 2, Ncol = 8)
distances = data.frame(Lew = 40, Lns = 30, H = 0)

gefShdAguiar <- calcGef(lat = lat, modeRad = 'prev', 
                        dataRad = gefAguiar, modeTrk = 'two', 
                        modeShd = c('area', 'prom'), 
                        struct = struct, distances = distances)
print(gefShdAguiar)

## End(Not run)