Energy return on investment (EROI) is a ratio used to evaluate the efficiency and viability of an energy source. It is calculated by dividing the total energy output of a system over its lifetime by the energy consumed to build, operate, and maintain that system. An EROI of less than 1 indicates a net energy sink. Fossil fuels traditionally boasted high EROI values that are gradually declining as extraction becomes more difficult.
Heard on the job
The proposed tar sands project was scrapped because the EROI dropped below 3 to 1 after accounting for the steam injection costs.
Also heard as
- EROEI