The debate about biogas has reached Catalonia loaded with mistrust, interests, and simplifications. It is normal for it to generate debate: we are talking about organic waste, livestock manure, industrial plants, transport, energy, and territory. But precisely because the topic is complex, it is advisable to avoid diagnoses that mix everything up and end up turning a waste treatment technology into the scapegoat for all the problems of the livestock model.Biogas is an organic waste treatment technology that allows a part of biogenic carbon (of biological origin) to be transformed into methane, a greenhouse gas much more potent than CO₂ in the short term, to be used energetically or molecularly, and to obtain a digested residue that can have fertilizing use if managed correctly. This process is not only for slurry: there is also municipal organic fraction, pruning and gardening waste, sewage sludge, agri-food waste, agricultural residues, food industry waste, and other organic flows that, in the context of climate emergency, must be treated anaerobically (in the absence of oxygen).This is the first misunderstanding. Presenting biogas plants solely as “energy factories” distorts the debate. Their primary function is environmental: to reduce methane emissions, a greenhouse gas dozens of times more potent than CO₂. Once digested, the waste does not release as much methane, it is a chemically more stable fertilizer, with less risk of pathogens and fewer volatile compounds that cause bad odors. The recovery of gas in the form of energy or molecularly is relevant, but it is a consequence of the valorization of a waste that needs to be treated, just like with wastewater treatment plants or municipal organic waste.Catalonia has a real problem of livestock concentration in certain areas, external dependence on feed, and pressure on soils and aquifers. Not all the impacts of the food and livestock model can be attributed to biogas: imported soy, cereals, mineral fertilizers, maritime transport, or agricultural machinery. These impacts exist and must be reduced. But they are not caused by the biogas plant. They are part of the livestock and food system. This problem must be addressed with livestock planning, territorial limits, herd control, strict compliance with nitrate regulations, and better connection between agriculture and livestock. But this debate is not resolved by rejecting anaerobic digestion outright. It is one thing to discuss what livestock model the territory can support, and another to decide how to best treat the manure and organic waste that are already generated.