Analysis of Hydrogen Production Methods using Electrolysis and Concentrated Solar Energy

The purpose of this work was to assess methods for hydrogen production using electrolysis and concentrated solar energy. The results of this work will bw used to guide future work in the application of concentrated solar energy to hydrogen production. Specifically, the objectives were to: 1) determine the cost of hydrogen produced from ambient temperature electrolysis and concentrated solarthermal energy, 2) compare these costs to those of hydrogen produced by ambient termperature electrolysis using photovoltaics and wind energy as the electricity source, 3) determine the cost of hydrogen produced from high temperature electrolysis and concentrated solar thermal energy and compare it to the cost of ambient temperature electrolysis. The first method that was analyzed was ambienttemperature electrolysis of water. In this method, concentrated solar energy is used to generate alternating current (ac) electricity which is supplied to the electrolyzer. Production of hydrogen is limited to the times when electricity is available from the solar power plant. The second method that was analyzed was high temperature electrolysis of steam. This method operates at about 1273 Kand, thermodynamically, requires less energy than ambient temperature electrolysis. In this method, a portion of the required energy can be supplied as thermal energy such that the solar plant may provide energy as both ac electricity and thermal.