Today, Steam Methane Reforming (SMR) produces more than 95% of the world’s H2. In conventional processes, the reaction is carried out at high temperature by burning 30-40% of the process gas and the efficiency is below 70%. Electrolysis is an alternative technology that is increasingly implemented, where renewable electricity is available. However, it suffers from high cost, up to 3 times when compared to SMR and low electricity to H2 efficiency (50-60%).
SOLARX partner CNRS recently demonstrated a unique solar-based microreactor for SMR, capturing the solar energy to supply heat to the endothermic SMR reaction achieving up to 85% efficiency, whereas producing H2 through electrolysis supplied with PV electricity has an efficiency limited to 15-25%. This can lead to a three to sixfold efficiency improvement in the use of the solar resource. Furthermore, the gas purity is very high (no burning residue), facilitating carbon capture and sequestration. In SOLARX, CNRS will modify these solar microreactors for compatibility with biogas, incorporate electrical heaters and integrate them into an H2 receiver that has the unique capability of operating either with solar or electrical energy.
The H2 receiver is based on building blocks that have been validated in conditions of high sunlight concentration, but SOLARX will upgrade these building blocks with additional electrical feed-in. Such a concept has been formulated at TRL2 but has not been demonstrated yet. The design and operating conditions will also be explored for reliable operation under dry methane reforming (consuming CO2). Through these upgrades SOLARX will increase the technology readiness levels of the innovations up to TRL 3 and TRL4.