Life cycle assessment based on exergy (exergy-based LCA)

The “exergy-based LCA” evaluation method, uses the exergy analysis associated with the entire production and consumption chain within the LCA. Exergy analysis is based on the second law of thermodynamics (the conditions under which the transformation of thermal energy into mechanical energy) and is used to avoid problems in energy analysis (eg identification of thermodynamic inefficiencies of processes) (N. Salehi et al, 2018 cited in Dewulf et al. 2008, Morosuk et al. 2016).

“Exergy” is defined as the maximum mechanical work that brings the system into thermodynamic balance with the environment.

“Energy” is defined as the ability of a physical system to perform mechanical work when moving from one state to another.

As a comparison of the terms “exergy” is dependent on the properties of the environment while “energy” is independent of the properties of the environment. “Exergy” can also be defined as a measure of energy quality while “energy” is defined as a measure of energy quantity (N. Salehi et al, 2018 quoted from Frangopoulos, 2009).