Showing 4 results for Electrolyze
Hadi Ghaebi, Behzad Farhang,
Volume 16, Issue 6 (8-2016)
Abstract
In the current work different organic rankine cycles (base and modified) coupled with proton exchange membrane presented to produce hydrogen and power. Organic rankine cycles used in this work are basic Organic Rankine Cycles (ORC), ORC incorporating regenerator, ORC incorporating feed fluid heater and ORC incorporating both of the regenerator and feed fluid heater. ORC energy demand supplied by geothermal energy. A thermodynamic model (energy and exergy) of systems done. EES software used to model the systems. Also a parametric study done to investigate the effects of the performance parameters (energetic and exergetic) of considered systems. The results showed that ORC incorporating both regenerator and feed fluid heater with PEM electrolyzer had the maximum energy (3.514%) and exergy (68.93%) efficiency in comparison with other systems. Also it can be observed that evaporator and electrolyzer had the most portion of exergy destruction of the system. Energy efficiency, exergy efficiency, hydrogen production and net power increased by pressure growth in all systems. The amount of exergy efficiency, energy efficiency, hydrogen production and net power increased by the evaporator temperature addition in ORC incorporating regenerator with PEM electrolyzer and ORC incorporating both regenerator and feed fluid heater with PEM electrolyzer but their amount marginally decreased by the evaporator temperature addition in basic ORC incorporating with PEM electrolyzer and ORC incorporating feed fluid heater with PEM electrolyzer.
Alireza Zahedi, Seyed Amirail Amirkhlili, Ali Ghaffari Nejad,
Volume 16, Issue 12 (2-2017)
Abstract
The wind is one of developing sources of renewable energy in recent years. Wind power often is unusable at peak times. Therefore, a storage system or backup power is always necessary. In this study, a hybrid system was applied for a wind turbine to provide the reliable power. The hybrid system consisted of four main components: a wind turbine, electrolyzer, hydrogen storage and fuel cell. The extra electricity produced in fewer demand hours by wind turbine was conducted to a hydrogen and oxygen generator system. Hydrogen were stored in a tank. Then, hydrogen was introduced to a fuel cell unit in order to produce electricity at peak times (when the electricity produced by wind power was less than demand). The hydrogen production rate by alkaline electrolysis as well as the electricity production by PEM fuel cell was investigated. The maximum hydrogen produced by the system per hour average was 304 ml and the power produced by the fuel cell was 1008 mW. After the construction of the prototype, a case study for this system was done in Kouhin area.
L. Hendooie , R. Shafaghat, A. Ramiar, M. Dardel, Q. Esmaili,
Volume 19, Issue 7 (7-2019)
Abstract
One of the most important factors in decreasing the lifetime and inappropriate performance of PEM electrolyzers is the non-uniform current distribution on membrane surface. Since the smoothest distribution of species and water leads to optimal current distribution, in this research, a 1D- 1D model has been developed that explores the distribution of species and water, and finally the current distribution in layers and determines the optimal performance conditions of the high PEM membrane electrolyzers. In this model, the pressure is assumed constant throughout the channel, the cell temperature is constant, and the membrane is fully hydrated. The length of the anode and cathode channels is divided into 20 equal parts. By simultaneously solving the equations along the channel and perpendicular to it in each section, the distribution of species and current are obtained. The result showed that by increasing the average flow density, the flow distribution is smoother along the channel and, with increasing water flow, the current distribution is smoothed, but it has little effect on the polarization curve. Fick's effect on the distribution of species at the interface between the membrane and the gas diffusion layer has been investigated. Finally, the effect of thickness on the polarization curve is determined. By increasing the thickness of the membrane and the electrodes, the function of the system decreases.
Seyed Mostafa Mirtabaei, Reza Shahraki Shahdabadi,
Volume 24, Issue 1 (12-2023)
Abstract
Hydrogen is considered as a new source of energy. One of the most used methods of hydrogen gas production is water electrolysis. Electrolysis of water by an electrolyzer and by passing an electric current through water molecules, using an intercellular membrane causes the breakdown of water molecules into hydrogen and oxygen. If the intercellular membrane is removed, hydrogen gas and oxygen are mixed and hydroxy gas is produced. This gas, which includes hydrogen and oxygen molecules, has been considered as an auxiliary fuel. For this purpose, in this research, the design and construction of a multi-cell electrolyzer producing hydroxy gas without a membrane using 316 steel sheet has been discussed. To increase the conductivity of water, potassium hydroxide electrolyte was used, and solar panels with different powers were used to supply the required energy consumption of the electrolyzer. Then, by conducting various experiments, the application of this technology using solar energy has been investigated. The results of the tests show that each electrolyzer plate has a voltage of 2 to 3 volts and there must be a proper proportion between the number of electrolyzer plates and the voltage of the panels. The production per solar panel surface for the three studied conditions was obtained as 1919, 4542.5 and 6919 liters per square meter, respectively, which indicates that there are optimal values corresponding to the panel surface and the area of the electrolyzer plates, which leads to an optimal current passing. It becomes more appropriate from the device and its performance.
