There is a growing interest for electrofuel processes among biogas producers, that can be associated with a potential for these processes to increase the profitability for biogas plants and make them more product flexible and less sensitive to market flutuations. However, the general view of the Swedish biogas industry is that it is difficult to overview the techno-economic performance and degree of maturity of the different processes. Knowledge about the technology readiness level (TRL) concern in particular the biological electrofuel processes.

Anna-Karin Jannasch, SP, has led an f3 project titled Electrofuels from biological processes – A knowledge synthesis that presents a knowledge synthesis on in-situ and ex-situ biological methanation and gas fermentation, using thermochemical methanisation as a reference. The possibilities to combine and/or to replace conventional biogas upgrading with the different electrofuel processes are also investigated and discussed.

The conclusions are that out of the investigated processes, thermochemical methanation is the most mature technology (TRL= 7-8), followed by Ex-situ biological methanation (TRL = 6-7), In-situ methanation (TRL=4-5) and biological gas fermentation (TRL=2-3). The report includes advantages as well as challanges for all technologies for comparison.

The report is written in Swedish, with a summary in English.