What drives the location and diffusion of biogas units?

In recent years, biogas units have become an important component of the energy transition, capable of converting waste and biomass into biogas. However, location is influenced by the efficiency and profitability of these biogas units. Previous research has focused on the economic, social, political, and environmental criteria for the siting of biogas units. Furthermore, studies have shown a tendency for co-location of eco-innovations, primarily due to the proximity of resources and the exchange of technical knowledge among neighbouring units (mimicry effects). However, this proximity can also lead to increased competition for local resources, potentially undermining the collective efficiency of the installations. This article aims to understand this paradox by exploring how the geographical proximity between units influences the siting of biogas units in the Brittany and Normandy regions. Using a Spatial Durbin model, we have examined the interactions between units and how these dynamics influence the factors affecting the probability of unit installation. Our results show that there are clusters of biogas units extending over approximately 17 kilometres. However, these effects are spatially limited: when the units are too close, competition for resources limits their installations, while when they are too far apart, the effect disappears.