Seminar Thijs de Groot

Alkaline water electrolysis is regarded as the cheapest and not mater water electrolysis technology, but it is often claimed to be less flexible than competing technologies. Yet, these claims are often poorly supported. It should be realized that in the past alkaline water electrlolysis did not have to be flexible, as it was used for baseload production of hydrogen based on continuously available hydropower. Therefore, the technology did not have to be flexible. The key question is wether the technology can be made flexible.
In this presentation, I will discuss three relevant types of flexibility, namely operating range (i.e. min load), ramp rates and shutdown tolerance. These types of flexibility connect to underlying physical processes such as gas crossover, gas holdup and reverse currents. How these processes limit flexibility will be discussed in detail. A "menu" of strategies to overcome these flexibility limitations will be presented. Yet, these strategies typically also comge at a price. Therefore, the key question is actually wether alkaline water electrolysis can remain cheap, while being also flexible.