After 10 years of composting, Jean-Luc Guigourese, a farmer in western France, decided to become a pioneer of anaerobic digestion. From the waste waters of his pig farm, the intermediate crops and from tomato waste, his biogas plant produces 450 kWh of electricity, which together with heat is sold to the nearby foundry. In addition to the owner, a specialized technician accompanied us during the visit, to outline the basic steps for maintaining the cogeneration system.