As global initiatives from COP 21 (the Paris Agreement) through to COP 30 continue to accelerate the electrification, diversification, and deep decarbonisation of energy systems, identifying practical alternatives to fossil‑derived fuels has become increasingly urgent. Synthetic methane, generated from waste or renewable CO₂ and renewable H₂, stands out as a near‑term, infrastructure‑compatible solution.
In this work, we focus on non‑thermal plasma methanation, a novel and rapidly emerging process that enables methane synthesis under ambient conditions, in stark contrast to the high‑temperature, high‑pressure requirements of conventional catalytic methanation. This emerging technology offers the potential for highly flexible, modular, and dispatchable renewable fuel production, representing a significant departure from traditional thermal routes.
The present study draws on the innovative plasma methanation systems developed through close collaboration with CSIRO Energy, whose experimental platforms have already demonstrated impressive performance. Building on this partnership, the current work evaluates the techno‑economic viability of this new plasma‑based technology. The plasma methanation systems utilised with CO2 and H2 flow rate of 1,667 m3/h, producing approximately 8.9 GJ/h of CH4.
Three different deployment scenarios were assessed: CO2 purchase with (a) H2 feedstock purchase, (b) on-site electrolysis, and (c) on-site electrolysis combined with a PV farm, and each scenario underwent detailed sensitivity analyses to determine the corresponding range of levelised cost. Plasma methanation presents a promising pathway toward global climate goals by utilising CO2 into synthetic methane, displacing fossil-derived gases, and enabling electrification of chemical synthesis.