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• Biogas upgrading is environmentally and energetically favourable over combustion. • Storage or utilisation of the captured CO 2 has larger savings than biogas upgrading. • Upgrading, CO 2 storage or utilisation perform well in all impact categories. • The energy system has a substantial impact on the environmental performance. • Methanation provides large climate change savings only in renewable energy systems. Biogas from anaerobic digestion is an important renewable energy source. Combining its utilisation with carbon capture and storage (CCS) or carbon capture and utilisation (CCU) may improve climate change performance. This study uses life cycle assessment to evaluate the environmental impacts of 17 biogas management technology configurations (TCs). The technologies include biogas combustion, upgrading to natural gas quality, CCS, direct utilisation of CO 2 and methanation. The focus is mainly on energy balances and climate change impacts, and the results are subjected to sensitivity-, uncertainty-, and energy system analysis. The TCs with CCS and CCU provide the largest climate change savings (-1400 to - 2100 kg CO 2 -eq/1000 Nm3 biogas). Specifically, the methanation TCs provide the highest savings, but they also depend strongly on the energy sources. When combustion and upgrading TCs are amended with CCS, the resulting climate change savings are robust across the energy systems. The biogas upgrading TCs exhibit substantial climate change savings, mainly due to the natural gas substitution. Combustion TCs without CCS have the lowest climate change savings and the highest quantified uncertainties. The biogas upgrading TCs with storage or direct utilisation of CO 2 provide a good compromise between climate change savings and energy recovery. In the remaining impact categories, the CCU TCs generally perform best, followed by the upgrading TCs and finally, the combustion TCs. The CCS TCs consistently perform worse than their counterparts without CCS, opposite to the climate change results. Overall, amending biogas utilisation with CCS or CCU can contribute to climate change mitigation. [ABSTRACT FROM AUTHOR]

The ever-increasing anthropogenic greenhouse gas (GHG) emissions worldwide make it quite challenging to meet country-specific Nationally Determined Contributions (NDC) targets. Therefore, it is evident that the existing emissions abatement measures need to be taken a step further. Internationally Transferred Mitigation Outcomes (ITMOs) are allowed in Article 6.2 of the Paris Agreement as a cooperative approach to achieving NDC goals. There is a potential to create ITMOs between Canada and China by replacing coal use in China with British Columbia (BC)'s liquefied natural gas (LNG) supply. Replacing coal with LNG in energy generation applications is a promising approach to mitigate emissions. With global and national pressures to reduce emissions, China has created a market for LNG imports to cater to its rising natural gas (NG) consumption due to the coal-to-gas source switching strategy. However, the terms under Article 6.2 requires generated ITMOs to ensure environmental integrity, support sustainable development goals, and have a robust accounting system. Therefore, the current study aims to quantify the life cycle environmental outcomes of generating ITMOs by exporting LNG from BC to Chinese end-users while integrating uncertainties and to provide policy recommendations in adherence with the requirements of Article 6.2. Different LNG export scenarios were generated in the study and environmental impacts of each scenario were assessed and compared using a life cycle assessment (LCA) framework developed by the authors. Sensitivity and uncertainty analyses were conducted to understand the impacts created by the data uncertainties in the final result. By replacing conventional coal with NG, approximately 40–45% and 26%–32% emissions reductions can be obtainable for Chinese textile and chemical industries, respectively. The highest emissions reduction of approximately 60% was observed when coal is replaced with NG for district heating. The life cycle emissions (LCE) quantification framework provided in the study provides stakeholders with a systematic approach to determine the total GHG emissions and emissions reduction potential of different LNG export scenarios. [ABSTRACT FROM AUTHOR]