Biogas units are a lever for energy transition, but their effects on agricultural incomes remain poorly understood and often poorly measured. A better understanding of these impacts is necessary, both because higher incomes can improve the sector’s social acceptability and because the profession currently lies at the center of public debate. Existing analyses focus mainly on the farms directly concerned, at the risk of selection bias, as these are generally larger and better capitalized. In this project, we assess the impact of opening a biogas plant on farm income and fertilizer consumption, considering crop rotation adjustments, whether farmers own the biogas plant. We also seek to identify the geographical areas most affected by their location.