Optimization of solar hydrogen systems based on hydrogen production cost

Hydrogen is regarded as a potential future energy carrier. It can be produc ed by the electrolysis of water with the required power supplied by a photo voltaic module. The hydrogen in this study was produced using a hydrogen ge nerator with a solid polymer electrolyte. The required power was supplied b y a photovolraic module rated at 3.4 V, 27.45 A. The experimental system wa s designed and constructed so that the photovoltaic module was directly cou pled to the hydrogen generator. The system characteristics: quantity of hyd rogen produced, current/voltage output characteristics of the PV module, PV module and H-2 generator temperatures were measured and analyzed. A method to design a solar hydrogen energy system, providing the most cost effectiv e hydrogen generation, was developed. In this method, the design point is c hosen based on the irradiance during system operation under rated capacity. The data supplied by the experimental system clearly showed the importance of considering the ratio of photovoltaic module cost to hydrogen generator cost when designing an optimum solar hydrogen system. (C) 2000 Elsevier Sc ience Ltd. All rights reserved.