Net Energy Gain (NEG) is a concept used in energy economics that refers to the difference between the energy expended to harvest an energy source and the amount of energy gained from that harvest. The net energy gain, which can be expressed in joules, differs from the net financial gain that may result from the energy harvesting process, in that various sources of energy (e.g. natural gas, coal, etc.) can be priced differently for the same amount of energy.
A net energy gain is achieved by expending less energy acquiring a source of energy than is contained in the source to be consumed. That is,
NEG = EnergyConsumable − EnergyExpended.
Factors to consider when calculating NEG is the type of energy, the way energy is used and acquired, and the methods used to store or transport the energy. It is also possible to overcomplicate the equation by an infinite number of externalities and inefficiencies that may be present during the energy harvesting process.
Alternatives are less reliable and provide less consumable energy, however they require a little less expended energy. Alternatives have slightly lower EROEI than fossil fuels.
· 9 years ago