Why is it in the News?

Developing a domestic manufacturing infrastructure for electrolyzers is expected to reduce the cost of green hydrogen and strengthen India's competitive advantage.

What are Electrolysers?

• Electrolysers are devices that produce hydrogen through a chemical process called electrolysis, which splits water molecules into hydrogen and oxygen molecules using electricity.

How do They work?

• These devices consist of a stack of conductive electrodes separated by a membrane, to which a high voltage and current are applied.
• This induces an electric current in the water, causing it to decompose into its constituents: hydrogen and oxygen.
• The generated oxygen is either released into the atmosphere or stored for future use as a medical or industrial gas.
• The hydrogen produced can be stored as a compressed gas liquefied for industrial use or utilised in hydrogen fuel cells, which power various transportation vehicles like trains, ships, and aircraft.

Types of Electrolysers:

• Alkaline Electrolysers: This technology, predominantly used by the fertiliser and chlorine industries, employs thick membranes and nickel-based electrodes.
  • It currently represents a significant portion of global electrolyser capacity.
• Proton Exchange Membrane (PEM) Electrolysers: Operating at high pressure, PEM electrolysers utilise thin perfluorosulfonic acid (PFSA) membranes.
  • Though they require gold and titanium-plated electrodes and catalysts like platinum, iridium, and ruthenium, they produce high-purity hydrogen and are easy to cool, making them a popular choice.
• Solid Oxide Electrolysis Cell (SOEC) Electrolysers: These devices utilise heat to produce hydrogen from steam and are ideal for locations with available heat sources such as nuclear or industrial facilities.
  • Operating at high temperatures ranging from 500 to 850 degrees Celsius.
• Anion Exchange Membrane (AEM) Electrolysers: Operating at significantly lower temperatures of 50 to 60 degrees Celsius, AEM electrolysers combine the less harsh conditions of alkaline electrolysers with the simplicity and high efficiency of PEM electrolysers.

Electrolyzers and Green Hydrogen Production:

• Green hydrogen is renewable hydrogen produced using water electrolysis technology and electricity generated from renewable energy sources, such as solar or wind.
• It is gaining unprecedented momentum globally, and it is believed that it is a key component in accelerating the shift to clean energy.
• The commercialization of electrolyzers can make green hydrogen more readily available and enable energy systems across the globe to undergo fundamental transformations to lower emissions and reduce their negative impact on the environment.