System approach and comparison of different technologies
The Green Hydrogen Production by Water Electrolysis

In order to produce hydrogen in large quantities, optimizing the active surface area is essential, but this alone is not sufficient to produce electrolysis capacity. It is therefore necessary to use several electrolysis cells (AME) simultaneously by stacking them in series in order to optimize the electrical power dissipated (used by the reaction) in relation to compactness. The electrochemical reactor consisting of a stack of several dozen or hundreds of cells is commonly referred to as a "stack," which operates according to the specific characteristics of each type of electrolysis.