EPFL engineers are taking part in PROMETEO – an EU research project to generate hydrogen on a large scale from renewable sources, in an effort to lower industrial carbon emissions.
Whether used as a fuel or as a storage medium, hydrogen is a perfectly clean energy source. However, the processes used to make it are not, since they still rely mainly on electricity or fossil fuels like oil, gas and coal. Under PROMETEO, an EU project launched earlier this year, engineers will work to develop a new system for the large-scale production of clean hydrogen, using only renewable energy sources. This would help lower the carbon emissions of many major manufacturing industries. Jan Van Herle's research group at EPFL Valais-Wallis in Sion is taking part in this initiative.
The idea is to build a prototype that uses electrolysis to extract hydrogen from water – the “H” in H2O. But rather than using water in its liquid form, as is normally done, the new system will use steam and solid oxide electrolysis (SOE) technology, which calls for temperatures of over 700°C. The heat and energy needed to run the prototype will come entirely from solar energy.
The prototype is expected to produce about 15 kg of hydrogen per day. To address the intermittent nature of solar energy resulting from variations in sunlight, the engineers will trial an innovative strategy for managing the various phases of energy conversion (electrolysis, generating electricity, and keeping the electrolyser in a "hot stand-by" mode). Their strategy involves minimizing drawdown from the power grid and increasing generation from stored renewables whenever solar energy (or wind energy, for the electrolysis phase) is unavailable.