Environmental impact assessment of the production of biomethane from landfill biogas and its use as vehicle fuel

Abstract

Biogas and biomethane are expected to play an increasing role in the short-term future of the energy market. It is imperative to identify alternative sources of these gases and minimize the utilization of those derived from fossil sources. One such source is biogas obtained from landfill gas, which can be subsequently upgraded to produce biomethane. This can then be used to replace the fossil natural gas for both energy generation and vehicle use. This paper employs the Life-Cycle Assessment methodology to analyze the environmental impact of the production of biomethane derived from landfill biogas. The objective was to identify the unit processes that have the greatest environmental impact. These processes were CO₂ removal, which contributed 84% to the impact category of 'global warming', and the second stage of biogas compression, which contributed 37% to the impact category of 'fossil resources scarcity'. Based on these results, we propose recommendations to reduce the environmental impact of both processes. Furthermore, an analysis was conducted on the use of biomethane as a vehicle fuel, which revealed that it has the potential to reduce the environmental impact of driving both light and heavy-duty vehicles in comparison with the use of diesel and petrol.