The production of hydrogen, vector of energy, by electrolysis way and by using photovoltaic solar energy can be optimized by suitable choice of electrolytes. Distilled water, usually used, due to membrane presence may be substituted by wastewaters, which enters more in their treatment. Waste water such as those of the Cleansing National Office, and also of the factories such as those referring with ammonia, the margines, and even urines that make it possible to produce much more hydrogen as distilled or salted water, more especially as they do not even require an additive or membranes: conventional electrolysers with two electrodes. This study seeks to optimize the choice among waste water and this, by electrolysis in laboratory or over the sun according to produced hydrogen flow criteria, electrolysis efficiency and electric power consumption. The additive used is NaCl. The most significant results are on the one hand the significant increase in the produced hydrogen flow by the addition of the additive; on the other hand the advantage of gas liquor and urine compared to the others tested electrolytes.
 S. H. Jensen, et al., “Hydrogen and Synthetic Fuel Production from Renewable Energy Sources,” International Journal of Hydrogen Energy, Vol. 32, No. 15, 2007, pp. 3253-3257. doi:10.1016/j.ijhydene.2007.04.042
 P.-H. Floch, et al., “On the Production of Hydrogen via Alkaline Electrolysis during Off-Peak Periods,” International Journal of Hydrogen Energy, Vol. 32, No. 18, 2007, pp. 4641-4647. doi:10.1016/j.ijhydene.2007.07.033
 L. Solera, J. Macanása, M. Mu?oza and J. Casado, “Elec trocatalytic Production of Hydrogen Boosted by Organic Pollutants and Visible Light,” International Journal of Hydrogen Energy, Vol. 31, No. 1, 2006, pp. 129-139. doi:10.1016/j.ijhydene.2004.11.001
 R. Ben Slama, “Production of Hydrogen by Electrolyse of Water and Photovoltaic Energy,” Proceeding of the 3rd International Congress on Renewable Energies and Environment CERE, Tunis, 6-8 November 2006.
 M. Cooper and G. G. Botte, “Hydrogen Production from the Electro-Oxidation of Ammonia Catalyzed by Platinum and Rhodium on Raney Nickel Substrate,” Journal of the Electrochemical Society, Vol. 153, No. 10, pp. A1894-A1901.
 F. Vitse, M. Cooper and G. G. Botte, “On the Use of Ammonia Electrolysis for Hydrogen Production,” Journal of Power Sources, Vol. 142, No. 1-2, 2005, pp. 18-26. doi:10.1016/j.jpowsour.2004.09.043