Analyzing Technological Trajectories in Biogas: A Main Path Analysis of Patent Citation Networks

The global energy crisis requires a trade-off between reducing the consumption of fossil fuels and exploring renewable alternatives. Biogas, obtained through anaerobic digestion, offers a sustainable solution for heat, electricity, and fertilizers. This paper analyzes the technological evolution of biogas using Main Path Analysis on European Patent Office (EPO) data since 1980. The development of biogas in Europe began in the 1970s, following the oil crisis, and has evolved gradually since that time. Despite its potential, limited research has explored its adoption and diffusion. Our study identifies eight distinct technological trajectories based on patent citation networks, shaped by the type of feedstock used. Recent innovations in the field include biogas upgrading, sensor technologies, modulable digesters, and increased biomethane production.