Fluctuations in wind and solar energy due to climate as well as the rising demand of renewable energy puts on and on a stronger focus on alternative systems like demand-driven biogas production. Hence, currently examined concepts for flexibilization of biogas plants are described. The biogas storage as well as the demand-driven biogas production by feeding management, variable conversion into electricity, disintegration processes or packed-bed fermentation belong to these concepts. Furthermore, the combination with power-to-gas or power-to-heat systems seems promising.