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ResumeUn des intérêts de la méthanisation est qu'elle peut participer à un recyclage extrêmement rentable des déchets. De fait, les collectivités ont un rôle à jouer dans ce processus car elles génèrent de nombreux types de déchets. Mais dans quelles mesures leur participation est-elle actuellement intéressante ? La volonté d'aboutir à une plus grande efficacité induit des changements de comportement de la part des foyers et des institutions. Quels sont-ils ?

In order to increase profits, all on-farm anaerobic digestion (AD) needs (i) waste with a high capacity to produce methane and (ii) an economic valorization of heat produce. This article shows that although local authorities produce organic waste: green waste, waste from restaurants, organic fraction from household refuse, urban sludge, green alga, etc. Few sources can be applied to on-farm AD because waste must have a high potential of methane, be sorted, stored within a close distance and have the possibility of payments in royalty fees: those advantages are difficult to cumulate. Nevertheless, examples show in the article are the expression of opportunity and could be further investigated. At the same time local authorities have many buildings with thermic needs which sometimes have very high consumption of heat and hot water. The added value of thermic energy produced by anaerobic digestion sometimes faces constraints, such as distance and urban density, which create high costs for heating networks. Opportunities of partnership between on-farm biogas production and local authorities are real but need to be studied on an individual case basis.