At “Energiepark Mainz” hydrogen will be produced by electrolysis. The energy necessary for this will partially be supplied by excess power of adjacent wind energy plants. The electrolysis works in an acidic environment with a solid polymer electrolyte.
In the process, liquid water is split into its components at the anode: for each molecule of water the reaction delivers half a molecule of oxygen and two protons. The oxygen molecules are collected on the side of the anode while the protons are transported via a conductive membrane to the cathode. The two protons build a single hydrogen molecule by absorbing two electrons at the cathode.