An electrolysis system includes at least one H.sub.2O electrolysis apparatus that electrolyzes water to produce hydrogen; and at least one CO.sub.2 electrolysis apparatus that electrolyzes carbon dioxide to produce carbon monoxide. The electrolysis system includes a co-electrolysis apparatus that co-electrolyzes water and carbon dioxide to produce less hydrogen per unit time than produced by the at least one H.sub.2O electrolysis apparatus and less carbon monoxide per unit time than produced by the at least one CO.sub.2 electrolysis apparatus.

An electrolysis system includes at least one H.sub.2O electrolysis apparatus that electrolyzes water to produce hydrogen; and at least one CO.sub.2 electrolysis apparatus that electrolyzes carbon dioxide to produce carbon monoxide. The electrolysis system includes a co-electrolysis apparatus that co-electrolyzes water and carbon dioxide to produce less hydrogen per unit time than produced by the at least one H.sub.2O electrolysis apparatus and less carbon monoxide per unit time than produced by the at least one CO.sub.2 electrolysis apparatus.

A controller and an operation control method for electrolysis stack module powered by a renewable energy power generation device and an electrolysis system using the same, the controller being configured to control power supply by receiving the power supply from a renewable energy generator and distributing the power supply to n (n≥2) electrolysis stacks, wherein, the controller is configured to determine whether or not to drive each electrolysis stack according to stack driving conditions, no less than two, determined on the basis of a preset minimum amount of operating power supply for each electrolysis stack, and the stack driving conditions are ranges of an amount of the power supply in which on/off of the electrolysis stacks is predetermined, and the controller is configured to control driving of the electrolysis stacks according to the stack driving conditions corresponding to the amount of supplied power from the renewable energy generator.

A controller and an operation control method for electrolysis stack module powered by a renewable energy power generation device and an electrolysis system using the same, the controller being configured to control power supply by receiving the power supply from a renewable energy generator and distributing the power supply to n (n≥2) electrolysis stacks, wherein, the controller is configured to determine whether or not to drive each electrolysis stack according to stack driving conditions, no less than two, determined on the basis of a preset minimum amount of operating power supply for each electrolysis stack, and the stack driving conditions are ranges of an amount of the power supply in which on/off of the electrolysis stacks is predetermined, and the controller is configured to control driving of the electrolysis stacks according to the stack driving conditions corresponding to the amount of supplied power from the renewable energy generator.

An electrochemical cell comprises a first electrode, a second electrode, and a proton-conducting membrane between the first electrode and the second electrode. The first electrode comprises Pr(Co.sub.1-x-y-z, Ni.sub.x, Mn.sub.y, Fe.sub.z)O.sub.3-δ, wherein 0≤x≤0.9, 0≤y≤0.9, 0≤z≤0.9, and δ is an oxygen deficit. The second electrode comprises a cermet material including at least one metal and at least one perovskite. Related structures, apparatuses, systems, and methods are also described.

A load testing device includes a connection unit to which a power source being tested is connected, a hydrogen generating unit that performs electrolysis based on power supplied from the power source being tested to generate hydrogen, two or more supply units to which hydrogen obtained in the hydrogen generating unit passes and to which a portable tank is removably attached, and an operational unit that has a load amount adjustment switch and a display unit. The load amount of the hydrogen generating unit is switched depending on an operational state of the load amount adjustment switch. The display unit displays at least one of an attachment status of the portable tank and a filling status of hydrogen in the two or more supply units.

A load testing device includes a connection unit to which a power source being tested is connected, a hydrogen generating unit that performs electrolysis based on power supplied from the power source being tested to generate hydrogen, two or more supply units to which hydrogen obtained in the hydrogen generating unit passes and to which a portable tank is removably attached, and an operational unit that has a load amount adjustment switch and a display unit. The load amount of the hydrogen generating unit is switched depending on an operational state of the load amount adjustment switch. The display unit displays at least one of an attachment status of the portable tank and a filling status of hydrogen in the two or more supply units.

Disclosed are a system and method for managing a self-contained hydrogen power system for a smart farm. The system may include a self-contained hydrogen generation unit configured to purify intake-water, generate clean hydrogen through water electrolysis, generate energy through a fuel cell by using the generated clean hydrogen, and store the energy, and a farm environment control unit configured to receive, from the self-contained hydrogen generation unit, energy for driving a plurality of sensors and devices for producing aquatic products and control an environment for producing aquatic products.

Disclosed are a system and method for managing a self-contained hydrogen power system for a smart farm. The system may include a self-contained hydrogen generation unit configured to purify intake-water, generate clean hydrogen through water electrolysis, generate energy through a fuel cell by using the generated clean hydrogen, and store the energy, and a farm environment control unit configured to receive, from the self-contained hydrogen generation unit, energy for driving a plurality of sensors and devices for producing aquatic products and control an environment for producing aquatic products.

Methods of making catalyst electrodes comprising sputtering at least Pt and Ir onto nanostructured whiskers to provide multiple alternating layers comprising, respectively in any order, at least Pt and Ir. In some exemplary embodiments, catalyst electrodes described, or made as described, herein are anode catalyst, and in other exemplary embodiments cathode catalyst. Catalysts electrodes are useful, for example, in generating H.sub.2 and O.sub.2 from water.