# Feedstock A `Feedstock` node defines a feedstock used in the production of fuels. Examples of feedstocks are natural gas and biomass. Example: ```python Feedstock "natural_gas" {} ``` A `Feedstock` node has no attributes or commands. It only defines the feedstock by name so that other nodes can refer to it. Feedstock-related values are set on the nodes that use the feedstock: * [Region](region.md): `set_feedstock_cost` and `set_feedstock_wtt` set the cost and WTT emissions of the feedstock in a region. * [Plant](plant.md): `set_feed_transport` and `set_feed_distance` set how the feedstock is transported to the plant and over what distance. * [Producer](producer.md): `set_feed_constraint` limits the amount of the feedstock available in a region in tons/year.