large quantities of low cost hydrogen free of carbon oxides are required as fuel for the hydrogen economy . commercial quantities of hydrogen can be produced from the electrolysis of water using a diaphragm - less electrolytic cell . the electrolytic cell has an anode cell and a cathode cell connected by a dc power source and an external conductor . an alternate apparatus method to produce hydrogen is to electrolyze water using unipolar activation . unipolar activation uses separate anode and cathode circuits and can use secondary cathode and anode cells to recover energy and produce further hydrogen .