PBtL fuels create post-EEG business model for biogas plants and enable 92% CO2 savings

A study by the renowned Technical University of Hamburg (TUHH) shows: The CO2 reduction potential of CAPHENIA’s PBtL fuels reaches up to 92% and thus surpasses classic power-to-liquid processes. The biomass potential in Germany is sufficient for at least 3.5 to 6.4 million tons of liquid fuels. This opens up an interesting post-EEG business model for biogas plants.

Researchers at the renowned TUHH chair of Prof. Kaltschmitt have analyzed the Power-and-Biogas-to-Liquid (PBtL) process developed by CAPHENIA in more detail in a study. The aim of the study was to investigate the environmental impact of a Power-and-Biogas-to-Liquid (PBtL) process with regard to the impact categories greenhouse potential, use of fossil resources, eutrophication potential as well as acidification potential and to compare it with a Power-and-Gas-to-Liquid (PGtL) process based on natural gas and a Power-to-Liquid (PtL) process. In addition, a study on available and unused biogas potential in Germany was carried out in order to map the business potential of such a process variant. Also, a need for action regarding the regulatory framework was identified.

The main results are summarized below:

  • Overall, there are large quantities of biogas that could be made available for fuel synthesis via a PBtL process. Amongst others, biogas from the electricity and heat sectors, which will not receive any further EEG subsidies in the foreseeable future, can be made available for transport as an alternative. In addition, biomethane can also be produced from previously unused substrates, thus increasing the total amount available. Using the mobilizable potential for fuel production, 3.5 to 6.4 million tons of liquid fuels could be made available per year.
  • The analysis of the Greenhouse gas (GHG) potential of the investigated processes showed that the lowest absolute emissions and thus the largest GHG reductions can be achieved with the PBtL process (92% CO2 reduction) and a PtL process (90%), respectively, when using electricity from offshore wind. The use of grid electricity (European electricity mix) for the production of synthetic fuels leads to significantly higher GHG emissions compared to the exclusive use of offshore wind power, but even then a CO2 reduction of 37% can still be achieved when applying the PBtL process. In contrast, the application of grid electricity in the PtL process leads to an increase in CO2 emissions to 2.6 times the fossil reference.
  • The analysis of the regulatory framework showed that an extension of RED II to include hybrid fuel groups would be purposeful, so that suitable quotas and calculation methods for GHG emissions can be defined. An addition of such fuel groups to RED II could provide legal clarity and investment certainty to developers and users of new technologies. The CAPHENIA process in particular could benefit from an adaptation of the RED II directive due to the high flexibility regarding the input materials.