Hydrogen and Electricity for Secondary Energy

Abstract

The hydrogen energy system using renewable energies as primary energies has the low environmental factor compared to the fossil energy system. In order to get a sustainable growth of our human society we have to get the green hydrogen energy system where hydrogen is produced from water using renewable energies. In the system the green hydrogen and electric energy are used for secondary energies and the conversion between hydrogen and electric energy is very important. The fuel cell and water electrolysis should be technically advanced further.