ISSN(Online): 2319-8753 ISSN (Print): 2347-6710 International Journal of Innovative Research in Science, Engineering and Technology (An ISO 3297: 2007 Certified Organization) Vol. 4, Issue 12, December 2015 Copyright to IJIRSET DOI:10.15680/IJIRSET.2015.0412105 12239 Experimental Study of Wave Shape and Frequency of the Power Supply on the Energy Efficiency of Hydrogen Production by Water Electrolysis Dhafer Manea. H. Al-Hasnawi 1 Alternative and Renewable Energy Research Unit, Technical Engineering College of Najaf, AL-FuratAL-Awsat Technical University, Najaf, Iraq 1 ABSTRACT:The purpose of this work is minimizing the electrical power dissipation during water electrolysis by fined the best frequency and wave form can be used in water electrolysis process. Where experimentally investigate the three wave forms are used namely, sine, triangular and rectangular. The effect of wave frequency is also investigated as well as the effect of amplitude and comparison between conventional DC power supply and rectangular wave form power supply to electrolysis. The results show the best efficiency factors of electrolysis and maximum volume flow rate of hydrogen product by using rectangular wave form in range (40Hz – 50Hz). Also using power source in the form of a rectangular wave can get high energy and faraday efficiency factors compared with using direct current. KEYWORDS:hydrogen production, water electrolysis, hydrogen fuel. I. INTRODUCTION One of the important application of renewable energy is used the hydrogen as fuel, high number of research work hard to use hydrogen energy because it clean, efficient, and available but the production of hydrogen is the problem. The research development and innovation activities that many industrial companies and research centres are developing the production of hydrogen by using water electrolysis [1–5]. Alfredo Ursu´a et al (2009) [6] ,They are used the different topologies of power supplies to analysis the energy consumption and efficiency of commercial alkaline water electrolyser, the first topology is used thyristor – based (ThPS) and the second topology is used transistor – based power supplies (TrPS). Where tested the commercial alkaline water electrolyser by two topologies (ThPS) and (TrPS), the results show that the cell energy consumption lower when it is supplied by the (TrPS) and increase efficiency. Shimizu et al.(2006) [7] conducted their experiment to test the behaviour of a cell while the voltage was applied in the form of ultra short pulses. Their goal was to reach higher cell power (increase the gas production rate) without reducing the efficiency. They placed platinum electrode plates 3 cm apart from each other in a 1M KOH aqueous solution. Electrolyte temperature was maintained to 293 ± 2 °K throughout the experiment. The results were compared for the cases of using a conventional DC, and an ultra-short pulse power supply with an output pulse width of about 300 ns. Output frequency and peak voltage of this power supply were adjustable from 2 kHz to 25 kHz and 7.9 V to 140 V respectively. Mazloomi S.K., NasriSulaiman (2012) [8] they are steady the factors that effect on water electrolysis efficiency such as electrolyte quantity, temperature, pressure, electrical resistance of the electrolyte, electrode material, separator material, and applied voltage wave form. Where in this paper used two applied voltage wave form, the first used conventional DC power supply and the second used an ultra-short pulse in frequency range (2 KHz 25 KHz) and