Supplying low-carbon electro-fuels and electro-chemicals: A life cycle assessment considering technological, geospatial, and temporal heterogeneities

Low-carbon liquid electro-fuels and electro-chemicals have emerged as important enabler for decarbonising the hard-to-abate sectors like transport and manufacturing industries. Here, we report the modelling of more than 10,000 liquid electro-fuels and electro-chemicals production configurations, supply chains, and technology development scenarios, to assess the trade-offs in life cycle greenhouse gas emissions, energy efficiencies, and water use. We explore approaches to quantify and minimise the emissions impact throughout the value chain, including accounting for embodied emissions from infrastructure and national and international supply chains, as well as the use of centralised and decentralised production strategies. The total loss of H 2 , energy requirements and water use in liquid electro-fuel supply chains typically ranged from 0.2–2.6% H 2 per kg fuel, 1.9–4.0 MJ per MJ fuel, and 0.016–0.118 L H 2 O per MJ fuel delivered, respectively. The life cycle greenhouse gas emissions (excluding embodied infrastructure emissions) of liquid electro-fuels, fully derived using renewable power, typically ranged from 1–21 gCO 2 e per MJ [0.02–0.92 kgCO 2 e/kg] in 2025, which could reduce to 1–10 gCO 2 e per MJ [0.02–0.43 kgCO 2 e/kg] in 2050, are generally within the EU and UK regulatory limits for transport fuels. Centralised production approaches minimise H 2 leakages in the supply chain and leverage the benefits of transporting energy-dense liquid fuels, while decentralised approaches could reduce energy consumption given that they could be integrated relatively easily with the distributed CO 2 sources. Accounting for embodied emissions from infrastructure can significantly increase overall greenhouse gas emissions, though they are generally still within regulatory limits for transport applications. Furthermore, other low-carbon electricity sources, such as nuclear power, hydro power, and certain combinations of grid and renewable electricity, can be used to achieve greenhouse gas emissions in line with regulatory limits, as long as the grid electricity is sufficiently decarbonised.