This study analyses the use of liquid, solid and gaseous biomass for power generation in Germany with respect to the Renewable Energy Sources Act (EEG), a significant policy instrument for promoting electricity generation based on renewable energy sources. The aim is the identification of bioenergy conversion pathways that have a low environmental impact and are cost-effective. To achieve this objective several research steps were undertaken, including a life-cycle analysis (LCA), economic analysis and the determination of the CO2 abatement costs. Besides, the authors show and discuss how a simplification of the environmental assessment by considering only the impact category greenhouse gases or the application of different calculation methodologies (i.e. allocation rules between electricity and heat produced) can affect the results. Overall the results show that the use of solid (wood) and gaseous biomass pathways causes both the lowest environmental impacts and electricity production costs when used for electricity generation. The choice of the modelling and calculation methodology may significantly influence the outcome (i.e. application of an exergetic allocation increases the environmental burden related to electricity generation). The lowest CO2-abatement costs were determined for the biodegradable waste pathway. (C) 2012 Elsevier Ltd. All rights reserved.