Energy colour palette

Returns a named vector of colours from a palette, in the style of RColorBrewer::brewer.pal(). The first argument selects the palette by name; energypal_info() lists what is available.

Usage

energypal(
  palette = NULL,
  n = NULL,
  file = NULL,
  order = NULL,
  direction = 1,
  include_groups = FALSE,
  include_carriers = TRUE,
  include_subtypes = FALSE,
  label_style = c("id", "short", "long", "default"),
  drop_na_colors = TRUE,
  unique_names = TRUE
)

Arguments

palette

Name of a built-in or registered palette. Defaults to the energypal.palette option, or "carriers".

n

Number of colours to return. NULL (default) returns all of them; otherwise the first n, and it is an error to ask for more than the palette holds.

file

Path to a palette file, taking precedence over palette.

order

How to sequence the colours. NULL or "spec" keeps file order; otherwise the name of an ordering declared in the palette ("carbon_intensity", "dispatchability", "merit_order", "renewability"), the name of a numeric property (sorted descending), one of the computed orderings "alpha", "hue", "lightness", "chroma", or an explicit character vector of entry names. See energypal_orders().

Presentation only. Orderings, and the numeric properties behind them, exist to arrange legends and chart series. They are indicative values, not validated figures, and must not be used in calculations.

direction

1 (default) or -1 to reverse the chosen order.

include_groups

Logical; include aggregate group entries such as FossilFuels (default FALSE).

include_carriers

Logical; include carrier or technology entries — the main level of the palette (default TRUE).

include_subtypes

Logical; include subtype entries such as Anthracite (default FALSE).

label_style

How to name the returned vector: "id" (canonical identifier, the default), "short", "long", or "default" (long if present, else short, else id).

drop_na_colors

Logical; drop entries with no colour (default TRUE).

unique_names

Logical; make the returned names unique by appending a numeric suffix to duplicates (default TRUE).

Value

A named character vector of hex colours.

Details

By default you get the palette's main level only — the carriers or technologies themselves, 17 of them for "carriers". The aggregate groups above them (FossilFuels, Renewable) and the subtypes below (Anthracite, Lignite) are available through include_groups and include_subtypes, but are off by default because a plotting palette wants distinct colours, and adjacent subtypes are deliberately near-identical.

Palettes are plain YAML files, so a project can supply its own via file = or energypal_register() and use it everywhere a built-in name works.

See also

energypal_info() to list the available palettes, energypal_table() for the underlying table, and energypal_colors() to map data labels to colours.

Examples

# The default carrier palette: 17 colours, one per carrier
energypal()
#>          FossilCoal           FossilOil           FossilGas           Bioenergy 
#>           "#2C2C2C"           "#8B4513"           "#4682B4"           "#228B22" 
#>               Hydro                Wind               Solar          Geothermal 
#>           "#0080FF"           "#87CEEB"           "#FFA500"           "#CD853F" 
#>     OtherRenewables             Nuclear         Electricity                Heat 
#>           "#32CD32"           "#FFD700"           "#1F4BA8"           "#CC5500" 
#>            Hydrogen HydrogenDerivatives      SyntheticFuels             Storage 
#>           "#00B5E2"           "#008FB4"           "#B5651D"           "#9370DB" 
#>               Other 
#>           "#C0C0C0" 

# A published report's colours, same identifiers
energypal("ipcc")
#>           FossilCoal            FossilOil            FossilGas 
#>            "#2E2E2E"            "#8B4000"            "#1E90FF" 
#>            Bioenergy              Nuclear        FossilCoalCCS 
#>            "#006400"            "#FFD700"            "#4D4D4D" 
#>         FossilOilCCS         FossilGasCCS         BioenergyCCS 
#>            "#A05A2C"            "#4682B4"            "#228B22" 
#> NonBiomassRenewables 
#>            "#98FB98" 

# Brewer-style: just the first few
energypal("eia", n = 5)
#> FossilCoal  FossilOil  FossilGas  Bioenergy      Hydro 
#>  "#3C3C3C"  "#8B4513"  "#6495ED"  "#90EE90"  "#00CED1" 

# Readable names for legends
energypal("carriers", label_style = "long")
#>                 Coal                  Oil          Natural Gas 
#>            "#2C2C2C"            "#8B4513"            "#4682B4" 
#>            Bioenergy  Hydroelectric Power                 Wind 
#>            "#228B22"            "#0080FF"            "#87CEEB" 
#>                Solar           Geothermal     Other Renewables 
#>            "#FFA500"            "#CD853F"            "#32CD32" 
#>              Nuclear          Electricity                 Heat 
#>            "#FFD700"            "#1F4BA8"            "#CC5500" 
#>             Hydrogen Hydrogen Derivatives      Synthetic Fuels 
#>            "#00B5E2"            "#008FB4"            "#B5651D" 
#>       Energy Storage                Other 
#>            "#9370DB"            "#C0C0C0" 

# The full hierarchy, groups and fuel subtypes included
length(energypal("carriers", include_groups = TRUE, include_subtypes = TRUE))
#> [1] 93

# What is available
energypal_info()$name
#> [1] "carriers"         "eia"              "epa"              "ipcc"            
#> [5] "owid"             "solaratlas_ghi"   "solaratlas_pvout" "technologies"    
#> [9] "windatlas_speed"