Streamlined life cycle analysis for assessing energy and exergy performance as well as impact on the climate for landfill gas utilization technologies

Three landfill gas (LFG) valorization technologies were compared using energy and exergy efficiency and a streamlined Life-Cycle Assessment (LCA) method. The technologies were (i) steam reforming and hydrogen utilization in an in situ cogeneration fuel cell (SR-IS-FCC), (ii) biogas utilization in an in situ gas engine cogeneration plant (IS-GEC), and (iii) amine scrubbing and biomethane utilization in an ex situ gas engine cogeneration plant (AS-ES-GEC). The SR-IS-FCC alternative recorded the highest exergy efficiency and savings in cumulative energy demand (CED), and the lowest global warming potential (GWP) when all the heat is utilized in situ; otherwise, the highest exergy efficiency and the lowest GWP and CED were associated with the AS-ES-GEC alternative. The results indicate that AS-ES-GEC is the preferential choice when heat cannot be utilized in situ. Otherwise, SR-IS-FCC records the best values for the three criteria, and the AS-ES-GEC technology is the least interesting alternative.