Hydrogen has been pinpointed by both the Scottish and UK governments as a fuel of the future.

Politicians are keen to scale up production of clean hydrogen to contribute to Scotland’s 2045 net zero target.

What is renewable hydrogen?

Renewable hydrogen comes in different forms.

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The purest sense of renewable hydrogen is green hydrogen, which doesn’t require fossil fuels. Other grades such as grey or blue hydrogen rely on natural gas (methane) to produce it.

Grey hydrogen, currently the most common form of the fuel, is created using steam methane reformation, splitting natural gas into hydrogen and carbon dioxide.

Blue hydrogen uses the same process, but the carbon dioxide is prevented from entering the atmosphere by carbon capture technology.

How is green hydrogen produced?

Green hydrogen is produced by using renewable electricity to power a process called electrolysis – which splits water molecules into hydrogen and oxygen.

The Herald: The process for creating green hydrogenThe process for creating green hydrogen (Image: SSE)

The fuel, if powered by renewable energy, has no carbon emissions, with oxygen the only by-product.

What can it be used for?

Those in the industry claim hydrogen can be used in a range of sectors of the economy.

The Herald: Hydrogen-powered busesHydrogen-powered buses

Buses and other vehicles such as trains can be powered by hydrogen to eliminate their contribution to the climate crisis, if a pure green grading is used.

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Trials have also been carried out to see if hydrogen could replace natural gas in fossil fuels boilers.

Heavy industry, such as chemicals plants at Grangemouth, hope to use hydrogen as a renewable fuel to cut carbon emissions through carbon capture and storage.

What is the Scottish Government’s hydrogen ambition?

The Scottish Government claims that up to 600,000 jobs can be created by scaling up hydrogen.

Under the Scottish Government’s current strategy, ministers hope to generate 5GW of power by 2030 and 45GW by 2045, when Scotland will become net zero.

What are the concerns about the fuel?

Climate campaigners have warned that focusing on hydrogen, particularly grey and blue hydrogen, allows fossil fuels giants to continue to burn gas and produce carbon.

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A report from WWF Scotland, revealed by The Herald in February, raised concerns that using hydrogen for heating homes was a “distraction” and called for the focus to be put on other methods, primarily heat pumps.

Fears have also been raised about the costs and energy needed to produce green hydrogen.