SynLink: Synthetic eFuels as key enabler for Sector Linking

At a glance

• Current methods for producing methanol from natural gas release considerable quantities of CO₂.
• Power-to-X processes, in which surplus green electricity is used instead of natural gas to capture CO₂ from air, to produce synthesis gas via electrolysis, and, lastly, to produce methanol or other commodity chemicals, are still associated with considerable costs at present and not suitable for use in industry.
• In the SynLink project, the project partners are thus investigating the whole process chain for methanol synthesis with the goal of being able to produce renewable fuels cost-effectively.

The challenge

Power-to-X projects are increasingly becoming a focus of research as the energy transition progresses. Such processes allow surplus electricity from renewable energy generation to be utilized for the production of commodity chemicals like methanol through the use of electrochemical processes like water electrolysis. At present, methanol is predominantly produced from natural gas and has a variety of applications: as a fuel additive, in direct methanol fuel cells (DMFCs), or as a raw material in the chemical industry. However, its production from natural gas releases significant quantities of CO₂.

Sustainable methanol production is still associated with considerable costs though. In addition, the developed processes are also not yet suitable for use in industry.

The solution

This is where the SynLink joint project comes in: the goal is the cost-effective production of renewable fuels, using methanol as an example, as well as long-chain hydrocarbons and alcohols. The project partners are investigating the whole value chain from the capture of CO₂ from air as a raw material to the subsequent production of synthesis gas via electrolysis right up to the production of fuels and their use in various mobile areas of application. Specifically, the project is employing a co‑solid oxide electrolyzer cell (Co-SOEC), which produces synthesis gas directly from water and CO₂ using electricity from renewable energies that can subsequently be converted into (e-)fuels via a variety of synthetic routes.

Fraunhofer IWES is responsible in a subproject for the scientific support of the further development of the CO₂ capture process via direct air capture (DAC) and electrolysis-based synthesis gas production on an industrial scale, among other tasks. 

The added value

Switching methanol synthesis over to renewably harvested molecules could avoid 1.53 tons of CO₂ emissions for each ton of methanol produced. Cost-effective production using surplus green electricity would not only mitigate CO₂ emissions by a significant amount but, with the appropriate flexibility in production facilities (DAC and Co-SOEC), also minimize the curtailment of renewable energy generation plants. Green methanol can be employed in areas of the transportation sector where solutions using batteries are not feasible, for example: in aviation and marine vessel propulsion. SynLink’s results will therefore make a key contribution to sector coupling and achieving climate neutrality.