An S4 class to represent a commodity

A commodity is a good or service that is produced and consumed in the model. The commodity class is used to store information about the commodity. All processes in the model operate on commodities, i.e. they either generate, produce, consume, transform, store, or transport commodities. The creation of a commodity object is done with the newCommodity function.

Slots

name

character. Name of the commodity.

desc

character. Optional description of the commodity for reference.

limtype

factor or character. The limit type of the commodity in balance equation, "LO", "UP", or "FX". "LO" by default, meaning that the level of commodity in the model is restricted with the lower bound, excess is allowed. "UP" means that the level of commodity cannot exceed the upper bound. "FX" means that total commudity supply and demand are equal, no excess or deficit is allowed.

timeframe

character. The default time-frame this commodity operates in the model. The lowest timeframe in the model is used by default.

geolevel

character. The geoscale level at which this commodity is balanced – the spatial counterpart of timeframe. The finest level in the model is used by default, reproducing the flat, single-level behaviour. Naming a coarser level (e.g. balancing steel nationally while electricity stays state-level) asserts free, unlimited transport of the commodity within that level, so it suits goods with a genuinely integrated market and never a network-constrained carrier such as electricity. Requires a geoscale on the model config; GLPK and GAMS only.

unit

character. The main unit of the commodity used in the model.

emis

data.frame. Emissions factors related to the commodity consumption (if "combustion" parameter of a technology which consumes the commodity is > 0).

comm

character. Name of the emitted commodity.

unit

character. Unit of the emission factor.

emis

numeric. Emission factor, emissions released per unit of the consumed commodity.

agg

data.frame. Used to define an aggregation of several commodities into the name commodity.

comm

character. Name of a commodity being aggregated.

unit

character. Unit of the commodity being aggregated.

agg

numeric. weight of the commodity in the aggregation, must be set for all aggregated commodities.

misc

list. List of additional parameters that are not used in the model but can be used for reference or user-defined functions. For example, links to the source of the commodity data, or other metadata.