The energy release component (ERC) is a number related to the available energy (BTU) per unit area (square foot) within the flaming front at the head of a fire.
Daily variations in ERC are due to changes in moisture content of the various fuels present, both live and dead.
Since this number represents the potential "heat release" per unit area in the flaming zone, it can provide guidance to several important fire activities.
As live fuels cure and dead fuels dry, the ERC values get higher, thus providing a good reflection of drought conditions.
The scale is open-ended or unlimited and, as with other NFDRS components, is relative.