Economic and Global Warming Potential Assessment of Flexible Power Generation with Biogas Plants

Demand-oriented power generation by power plants is becoming increasingly important due to the rising share of intermittent power sources in the energy system. Biogas plants can contribute to electricity grid stability through flexible power generation. This work involved conducting an economic and global warming potential (GWP) assessment of power generation with biogas plants that focused on the Austrian biogas sector. Twelve biogas plant configurations with electric rated outputs ranging from 150-750 kW and different input material compositions were investigated. The results from the economic assessment reveal that the required additional payment (premium) to make power generation economically viable ranges from 158.1-217.3 Euro MWh(-1). Further, the GWP of biogas plant setups was analyzed using life cycle assessment. The results range from -0.42 to 0.06 t CO2 eq. MWh(-1) and show that the 150 kW plant configurations yield the best outcome regarding GWP. Electricity from biogas in all scenarios outperformed the compared conventional electricity sources within the GWP. Greenhouse gas (GHG) mitigation costs were calculated by relating the needed premium to the CO2 eq. saving potential and range from 149.5-674.1 Euro (t CO2 eq.)(-1).