Sustainable regional biogas networks in Southern Brazil

Abstract Biogas production from livestock manure has been implemented on large farms in many regions for generating energy while curbing air and water pollution that otherwise results from untreated manure. Traditional biogas systems have required subsidies for implementation on large farms, while implementation on small farms remains rare. Using a new non-linear optimization model with validated field data from Southern Brazil, we explore the feasibility of manure-to-energy systems with cooperative collection and energy production. We generate technical designs for several regions while accounting for costs and greenhouse gas emissions. Our results indicate that profitable and environmentally responsible biogas networks are possible for the areas studied. In one case, a consortium of 26 municipalities in Parana, Brazil, may generate 718 million m 3 of biomethane while offsetting 10.5 billion kg of CO 2 equivalent greenhouse gas annually, with profits up to US$250 million. Results show that municipality-level biomethane production is more profitable than electricity generation and highlight the need for concurrent policy and technical design for enabling viable biomass to energy systems.