Aiming to assess the sustainability of a terminating swine production system, an energy efficiency study was carried out through a 120 days animal lot in a commercial system at Ouro Verde do Oeste, in the State of Paraná, Brazil. The energy rate of each compound involved in the production process and waste treatment using a biodigestor (input and output) was quantified. The matrixes of energy consumption were determined in the form of animal feeding, electrical energy, human labour, equipment, structures, alive swine production, biofertilizer production and biogas. The results indicated that the activity corresponded to an industrial agroecosystem, highly specialized, importing a great part of the energy consumed in the production process and applied to the exportation, with energy efficiency of 0.38 (Joutput/Jinput). In direct input energy, 95.3% correspond to animal feeding, 4.6% to the piglets, while in energy output 56.8% corresponded to the terminating swine, 30.1% to biofertilizer and 13% to biogas.
energy input and output; anaerobic digestion; farm structures
