Renewable fuels and chemical products, produced from renewable electricity and CO₂, are considered a promising climate-neutral solution for the chemical industry and mobility. To produce these raw materials, the Dresden-based H₂ company Sunfire develops one of the most efficient co-electrolysis technologies.

To become independent of fossil fuels, industry, gas suppliers and mobility need low-emission solutions. The Kopernikus P2X project, funded by the German Federal Ministry of Education and Research (BMBF), is examining one of the most promising approaches: Power-to-X technologies. These innovative solutions convert renewable electricity into other forms of energy, such as green H₂ or renewable fuels.

The high-temperature co-electrolysis plant of the H₂ company Sunfire is an important part of the research project that is now in its second funding phase. The Dresden-based company has recently achieved another technological milestone: after a project duration of around three years, the plant's factory acceptance test has been successfully completed.

With this, Sunfire put its new generation of co-electrolysis into operation for the first time. The unique feature of this innovative technology is the particularly efficient process, in which synthesis gas – a mixture of H₂ and carbon monoxide – is produced in just one step using renewable electricity from water steam and CO₂. The whole process takes place at high operating temperatures of up to 850°C.

Within the FAT, an output of up to 220 kW with an electrical efficiency of more than 85 %LHV was achieved, which represents a significant increase compared to the proof-of-concept system of the first project phase (10 kW). Sunfire relied on significant operational experience from the recently completed SynLink research project funded by the German Federal Ministry of Economics and Climate Protection. As part of the project, the Dresden-based company developed and validated a co-electrolysis module in the 150-kW size class.

The renewable synthesis gas produced by co-electrolysis can be further processed in a downstream step into alternative fuels, waxes or other chemical products. For this purpose, the electrolyzer will be delivered to the Karlsruhe Institute of Technology at the beginning of the year and integrated into a power-to-liquid plant at the Energy Lab 2.0. The project partners aim to produce around 200 liters synthetic fuels per day with the integrated plant over the course of several campaigns.