What is green hydrogen and why is it touted as a clean fuel?

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Green hydrogen is being touted around the world as a clean energy solution to take the carbon out of high-emitting sectors like transport and industrial manufacturing

BENGALURU, India — Green hydrogen is being touted around the world as a clean energy solution to take the carbon out of high-emitting sectors like transport and industrial manufacturing.

The India-led International Solar Alliance launched the Green Hydrogen Innovation Centre earlier this year, and India itself approved $2.3 billion for the production, use and export of green hydrogen. Global cooperation on green hydrogen manufacturing and supply is expected to be discussed by G-20 leaders at this week's summit in New Delhi.

Hydrogen is produced by separating that element from others in molecules where hydrogen occurs. For example, water — well known by its chemical symbol of H20, or two hydrogen atoms and one oxygen atom — can be split into those component atoms through electrolysis.

Hydrogen has been produced and used at scale for over a century, primarily to make fertilizers and plastics and to refine oil. It has mostly been produced using fossil fuels, especially natural gas.

But when the production is powered by renewable energy, the resulting hydrogen is green hydrogen.

The global market for green hydrogen is expected to reach $410 billion by 2030, according to analysts, which would more than double its current market size.

However, critics say the fuel is not always viable at scale and its ‘green’ credentials are determined by the source of energy used to produce it.

Green hydrogen can have a variety of uses in industries such as steelmaking, concrete production and manufacturing chemicals and fertilizers. It can also be used to generate electricity,