Development of an operation strategy for hydrogen production using solar PV energy based on fluid dynamic aspects

Abstract

Alkaline water electrolysis powered by renewable energy sources is one of the most promising strategies for environmentally friendly hydrogen production. However, wind and solar energy sources are highly dependent on weather conditions. As a result, power fluctuations affect the electrolyzer and cause several negative effects. Considering these limiting effects which reduce the water electrolysis efficiency, a novel operation strategy is proposed in this study. It is based on pumping the electrolyte according to the current density supplied by a solar PV module, in order to achieve the suitable fluid dynamics conditions in an electrolysis cell. To this aim, a mathematical model including the influence of electrode-membrane distance, temperature and electrolyte flow rate has been developed and used as optimization tool. The obtained results confirm the convenience of the selected strategy, especially when the electrolyzer is powered by renewable energies.

Simple and Precise Approach for Determination of Ohmic Contribution of Diaphragms in Alkaline Water Electrolysis

“…AWE polarization curves, using Zirfon ® as diaphragm, were carried out in an electrochemical cell (MicroCell, Electrocell A/S, Tarm, Denmark) integrated in an AWE test bench designed and constructed by CNH2 (National Science Foundation, Alexandria, VA, USA) [1,3]. Current was applied by a power source (Elektro-Automatik EA-PSI 6000, EA Elektro-Automatik GmbH & Co.KG, Viersen, Germany), and both potential and current were monitored by a Supervisory Control and Data Acquisition (SCADA) system developed by CNH2.…”

“…From a technical point of view, different technologies may be considered to perform water electrolysis, such as: Alkaline (AWE), proton exchange membranes (PEMWE), and solid oxide (SOWE) electrolysis. Among them, AWE is considered an optimal solution for RE combination, because it is the most economical and mature technology for H 2 electrochemical production, especially at a large scale [3]. In fact, the largest water electrolysis systems are, nowadays, alkaline electrolyzers.…”

A versatile and membrane-less electrochemical reactor for the electrolysis of water and brine

“…This is why optimizing the electrolyte flow rate in alkaline cells is crucial before deploying them in the power-to-gas industry. 65 Besides the advantages of Fig. 2 The membrane-less reactor of this study is tested for two electrochemical reactions: (a) water electrolysis and (b) brine electrolysis.…”

CFD Modeling and Experimental Validation of an Alkaline Water Electrolysis Cell for Hydrogen Production

“…To solve the different equations described above, the following simplifications were considered in order to improve convergence and reduce the computational cost of the model [5,9,32]:…”

“…Furthermore, hydrogen can be transported by its own hydrogen distribution grid as admixture in the natural gas grid, or it can be also stored in appropriate facilities. When required, hydrogen can be efficiently transformed into electricity by fuel cells and returned to the electricity 2 of 17 grid or used as fuel for the transport sector or even for new industrial processes [4,5]. In this way, electrolysis enables large scale production of green hydrogen and electrical energy storage.…”