Electrolyzer development

There are no electrolyzers developed specifically for operation with wind turbines. However, the rapid response of electrochemical systems to power variations makes them suitable "loads" for wind turbines. Industrial electrolyzers are designed for continuous operation, mainly because their elevated investment cost requires high-capacity factors for reasonable payback times, but they are subject to a considerable number of current interruptions through their lifetime due to occasional power interruptions, accidental trips of safety systems, and planned stops for maintenance. Current interruptions are more frequent in specialty applications, where electrolyzers supply hydrogen "on demand." Therefore, the discontinuous use of the equipment is not new, and most commercial electrolyzers may be used in intermittent operation although a significant performance decrease is expected with time. In fact, it is not power variation, but current interruptions that may cause severe corrosion problems to the electrodes, if the latter are not protected by the application of a polarization current when idle. 

Figure 3. Picture of HyLYZER 2.0 Module PEM electrolyzer developed by Hydrogenics Corp.

The electrochemical reaction proceeds most effectively in the presence of a catalyst, and the nature of the catalyst can have a significant effect upon the electrode overpotentials. As a matter of convenience, all of the early work in the electrolyzer development used platinum as both the anode (SO2 oxidation electrode) and cathode (H2 generation electrode) catalyst. It was recognized, however, that although platinum might be a technically satisfactory catalyst for the cathode, it was only marginally suitable as the anodic catalyst. 

Electrolyzer designs historically have emerged from particular industries. Their design parameters and requirements are quite different than what is needed to produce hydrogen from renewable energy sources. That said, there is a lot that can be learned from electrolyzer development over the years, but there is plenty of room for electrolyzer innovation, especially for those designed to operate with renewable energy power sources. 

Hydrogenics HyLYZER/25 bar 1 MW electrolyzer (development stage) 1 0-260 4.9 (stack) 7.2 (system) Not yet published 0-100... 

However, it was not until 1948 that we would see the first pressurized industrial electrolyzer, developed by Ewald Amo Zdansky for the Swiss group Lonza, and 1951 saw the commercialization of the first high-pressure electrolyzer (30 bars) by the German company Lurgi, who had acquired Lonza s patent. 

In another development (32), the sodium sulfate solution produced during the desulfurization of paste with caustic soda is electrolyzed in a membrane ceU to produce caustic soda and high purity sulfuric acid. The caustic soda is recycled to the desulfurization stage the sulfuric acid, after concentration, can be reused in battery production. 

Aluminum, though the third most abundant element, was quite expensive until about 1886, when a practical commercial electrolysis process was developed by a young American chemist, C. M. Hall. Bauxite, A1203-jcH20, is dissolved at about 1000°C in molten cryolite, Na3AlF6, and electrolyzed. 

Charles Hall was inspired by his chemistry professor at Oberlin College, who observed that whoever perfected an inexpensive way of producing aluminum would become rich and famous. After his graduation. Hall set to work in his home laboratory, trying to electrolyze various compounds of aluminum. He was aided by his sister Julia, who had studied chemistry and shared Charles interests. Julia helped to prepare chemicals and witnessed many of the electrolysis experiments. After only eight months of work. Hall had successfully produced globules of the metal. Meanwhile, Heroult was developing the identical process in France. 

The Volta pile was of extraordinary significance for developments both in the sciences of electricity and electrochemistry, since a new phenomenon, a continuous electric current, hitherto not known, could now be realized. Soon various properties and effects of the electric current were discovered, including many electrochemical processes. In May of 1800, William Nicholson and Sir Anthony Carlisle electrolyzed... 

The development goals for water electrolyzers are oriented toward increasing the efficiency and reducing the cost. Most of the issues to be addressed are not specific to intermittent power operation. The efficiency of water electrolysis increases with the increasing... 

The Hydrogen Research Institute in Canada has developed and tested a stand-alone renewable energy system composed of a 10 kW wind turbine, a 1 kWpeak photovoltaic array, a 5 kW alkaline electrolyzer, and a 5 kW PEM fuel cell. The components of the system are electrically integrated on a 48 V DC bus [50]. 

Standards Development Electrolyzers UL, CSA Reformers UL, CSA, API Performance Test Procedures ASME, CSA Chemical Hydrides UL, CSA.NFPA... 

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