The annual maintenance costs for alkaline water electrolyzers are lower than those of PEMEL systems.

 The annual maintenance costs for alkaline water electrolyzers are lower than those of PEMEL systems. The main maintenance required for alkaline electrolyzers is draining and refilling the electrolyte, which should be done once a year or when the electrolyte's quality degrades. The used electrolyte should be disposed of in accordance with local regulations. Other maintenance tasks include: 

Checking that the ventilation ports are free of dust and obstacles

Ensuring there are no leakages

Here are some other things to know about alkaline water electrolyzers:

Lifetime

Alkaline water electrolyzers have a lifetime of 20–30 years. 

Investment costs

The investment cost for alkaline water electrolysis is typically between USD 500–1000/kW. 

Efficiency

Commercial alkaline electrolyzer systems have efficiencies ranging from 43–69%. 

Production capacity

The production cost of alkaline water electrolysis can vary from 2.6 to 12.3$/kg. 

Advantages

Alkaline water electrolyzers have low capital costs, are available in large plant sizes, and have long life spans. 

Disadvantages

Alkaline water electrolyzers have low current density and high maintenance costs