Comparison of Environmental Impact of Two Different Bioelectricity Conversion Technologies by Means of LCA

Between the energy sources biomass waste is considered more and more important and the choice of the most appropriate energy conversion process is essential. The present paper presents a study for biomass waste to two distinguished energy conversion processes and the comparison of their environmental impact. The considered processes are gasification combined with internal combustion engine for power generation and combustion combined with an Organic Rankine Cycle (ORC) system with same electric power and same biomass flow as input to the conversion process. First, energy analysis of both mentioned systems have been investigated by means of Aspen Plus simulation. In the next step, model output is applied to evaluate the environmental profile of these small-scale biomass-based energy production systems. Environmental performance from cradle-to-gate was carried out by life cycle assessment (LCA) methodology. Results reveal that biomass production has a high influence over all impact categories. In both systems, eutrophication (EP), acidification (AP) and global warming potential (GWP) were identified as the main impacts. As a result, ORC system entails higher environmental burdens in all impacts categories.