Exergy life cycle assessment model of “CO2 zero-emission” energy system and application

An exergy life cycle assessment (ELCA) model based on life cycle assessment (LCA) and exergy methodology was developed to assess a 2×300 MW coal-fired power plant, and the results indicated that the exergy input in operation phase of power plant accounts for 99.89% of the total input and only 0.11% in construction and decommission phases. Direct and indirect exergy inputs account for 93.03% and 6.97%, respectively. Compared with coal-fired power generation system before carbon emission reduction, exergy input-output ratio of life cycle “CO2 zero-emission” energy system and exergy efficiency are about 5.563 and 17.97%, respectively, which increases by 62.47% and declines by 11.21% approximately. The model quantifies the energy, resource consumption and pollutant emissions of system life cycle using exergy as the basic physical parameter, which will make the assessment more objective and reasonable.