Solid Oxide Electrolyser Demonstrator Development at Elcogen
Authors: Lehtinen Timo , Noponen Matti 
Published: July 2021

Elcogen is a company providing solid oxide cell and stack solutions for fuel cell (SOFC) and electrolysis (SOEC) applications. Elcogen’s solutions are designed to operate at reduced operating temperatures but still providing high performance at affordable cost and low degradation level. Elcogen is currently expanding its manufacturing capabilities towards multi-MW annual production levels through a factory project. As a part of commercialization tasks, Elcogen is developing a demonstrator unit for steam electrolysis applications producing green hydrogen. This demonstrator unit is a part of an EU’s H2020 funded C2FUEL project. C2FUEL project aims to develop energy-efficient, economically and environmentally viable CO2 conversion technologies for the displacement of fossils fuels emission through a concept of industrial symbiosis between carbon intensive industries, power production, and local economy. The key technical and economic challenges to be tackled in the project are related to innovative production routes of dimethyl ether (DME) and formic acid (FA) from hydrogen (produced by Elcogen’s technology) and captured carbon dioxide. The C2FUEL concept will be demonstrated at Dunkirk industrial area between DK6 combined cycle power plant, Arcelor Mittal steel factory and one of the major European harbours.

This presentation outlines the current progress of the high temperature electrolysis demonstrator development at Elcogen. The main advantage of high temperature solid oxide electrolysis technology compared to low temperature electrolysis technologies, i.e. polymer electrolyte membrane and alkaline, is its considerably higher electrical efficiency and thus reduced specific energy consumption. E.g. the specific energy consumption for a SOEC stack can be up to 25 - 45% better than for PEMEC and AEC technologies and even in complete system level SOEC technology can provide 15 – 45 % better efficiencies [1]. The electrolyser demonstrator unit is designed to deliver 1 Nm3/h of hydrogen at 40 bar. The electrolysis stack is Elcogen’s own technology and it is operated at about 700°C. The processes for steam and gas supply, and heat management are implemented with standard industrial components. The gas pressurizing is conducted with a mechanical compressor which has an inherent feature to produce pressure variation on the suction side. Minimization of this pressure variation is conducted with system level solutions. Prior the compression stage, hydrogen is dried in order to provide high quality hydrogen to the synthesis processes and to avoid water condensation in the pressurized components. The demonstrator is divided into two subsystems: electrolyser subsystem that produces atmospheric pressure hydrogen and compressor subsystem which compresses the produced hydrogen to 40 bar. The subsystems are designed modular and can be operated also freely from each other.

This work has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 838014 (C2FUEL).

References

[1] O.Schmidt, A. Gambhir, I. Staffell, A. Hawkes, J.Nelson, S.Few, “Future cost and performance of water electrolysis: An expert elicitation study”, International Journal of Hydrogen Energy, 42 (52) 28.12.2017, pp. 30470-30492.