Climate impacts of sourcing CO₂ from biogas plant for breweries: A comparative life cycle assessment

This report examines three different carbon dioxide (CO2) supply chains for the beverage industry and compares their climate impacts using life cycle assessment (LCA). The assessment is conducted for one tonne of liquid CO2 delivered to a brewery. The supply chains studied are biogenic CO2 from biogas plants (Bio), CO2 produced as a by-product of ammonia production (Fossil by-product), and CO2 generated from propane combustion (Fossil burn). The system boundary was cradle-to-gate. Climate change impacts were assessed using the CML 2001 method through global warming potential with a 100-year time frame (GWP100). In addition, a sensitivity analysis was carried out to evaluate the effect of transport distance on the results. For the base-case transport distance (51 km), the climate impacts were 43 kg CO2-eq/t for Bio-scenario, 217 kg CO2-eq/t for CO2 Fossil by-product scenario, and 1322 kg CO2-eq/t for Fossil burn scenario. In the Bio-scenario, most of the climate impact is caused by electricity consumption for CO2 purification and liquefaction, whereas in the Fossil by-product scenario, the largest impact originates from the upstream burden allocated to CO2 from the ammonia production process. In the Fossil burn scenario, direct emissions from combustion dominate the impacts. Based on the results, it can be concluded that biogenic CO2 from biogas plants can offer a more climate-friendly option for meeting the CO2 demand of breweries, with this advantage maintained even at long transport distances.