Cost analysis of concepts for a demand oriented biogas supply for flexible power generation

•Costs of a demand oriented biogas supply for flexible power generation.•Short term biogas supply is preferably done by on site biogas storage concepts.•Flexible biogas production concepts benefit from a reduced gas storage demand.•Press fluid from fibre-rich grass silage is used to adapt the biogas production.•Substrate costs are identified to have the biggest effect on biogas supply cost. With the share of intermittent renewable energies within the electricity system rising, balancing services from dispatchable power plants are of increasing importance. Highlighting the importance of the need to keeping fuel costs for flexible power generation to a minimum, the study aims to identify favourable biogas plant configurations, supplying biogas on demand. A cost analysis of five configurations based on biogas storing and flexible biogas production concepts has been carried out. Results show that additional flexibility costs for a biogas supply of 8h per day range between 2€ and 11€MWh−1 and for a 72h period without biogas demand from 9€ to 19€MWh−1. While biogas storage concepts were identified as favourable short term supply configurations, flexible biogas production concepts profit from reduced storage requirements at plants with large biogas production capacities or for periods of several hours without biogas demand.