The effects of incorporating renewable energy into the environmental footprint of beef production

Abstract

This study quantifies the influence of the on-farm implementation of different energy mitigation systems, anaerobic digestion (AD) for biogas production and rooftop photovoltaics (PV), and assesses the environmental and energy impact on beef cattle production. Data on technical aspects were collected and a cradle-to-farm gate life cycle assessment approach was adopted. Two baseline production scenarios, with conventional manure and slurry management (considering different slurry storage: open or covered), were compared with three alternatives: (i) with the implementation of AD plant only; (ii) with the implementation of a PV system only; and (iii) with both. Impacts on the infrastructure and operation of AD plant and PV systems were considered, as well as their influence on emissions and electricity generation. The latter was managed with a system expansion, considering an environmental credit. The results, expressed per 1 kg of live weight of beef cattle produced, showed widespread improvements across the impact categories assessed. The AD scenario presented larger mitigations than the PV system alone, but the best result is achieved when both energy systems are implemented, with global warming potential reduced by 12 % and fossil resource scarcity by 35 %. This work represents a benchmark for future life cycle analysis of renewable energy system implementation for livestock.