Based on on-site observations and more than 70 sociological interviews with farmers in the Grand Est region conducted from November 2022, this paper explores the ambivalent perception of the “German model” of anaerobic digestion, which is both held up as an example due to its earlier implementation and criticized for encouraging agricultural intensification. Analysis of the development of biogas plant manufacturers – mostly German companies – reveals the cross-border circulation of references from Germany to France and sheds light on the role played by these go-betweens and visits to biogas plants on the dissemination of technologies to the Grand Est region. The paper, then, offers a sociological reflection on the processes of local and professional adaptation and appropriation of anaerobic digestion models, which makes it possible to go beyond the simplistic opposition between farmers and energy providers. This study ultimately draws attention to the tension, both in Germany and France, between the two goals of decarbonizing the economy and achieving environmental sustainability – in other words, between energy and ecological transition – revealing complex spatio-temporal dynamics in the development of the on-farm anaerobic digestion sector and providing for a better understanding of current and future challenges.