
Hydrogen is a naturally occurring gas, and it is the most abundant substance in the universe. (The word in Greek means “water former” because hydrogen creates water when burned.) Clean hydrogen is hydrogen produced with very low or zero carbon emissions. The term also refers to derivative products of hydrogen, including clean fuels.
Green hydrogen is hydrogen derived from renewable energy and water. It’s produced using a process called electrolysis, wherein electricity from renewable sources is used to split the hydrogen molecules from the oxygen molecules in water. Because the electricity used here comes from renewable sources, there are no greenhouse-gas emissions.
Green hydrogen can be used to decarbonize hard-to-abate sectors such as industry and heavy transport. The industrial sector often requires high heat for production, and green hydrogen is a strong candidate to decarbonize high-heat industrial processes, such as manufacturing steel, chemicals, and cement. Green hydrogen can also be used to decarbonize chemical production processes such as ferric iron reduction, municipal waste incineration, biomass gasification, fermentation, pulp production, biogas upgrading, and calcination.
The role of hydrogen in the future is a topic of great interest. According to the International Energy Agency (IEA), hydrogen has the potential to play a significant role in achieving a clean, secure, and affordable energy future. The IEA’s report finds that clean hydrogen is currently enjoying unprecedented political and business momentum, with the number of policies and projects around the world expanding rapidly. The report concludes that now is the time to scale up technologies and bring down costs to allow hydrogen to become widely used.
Hydrogen can be used in sectors where it is almost completely absent, such as transport, buildings, and power generation. Hydrogen can reduce CO2 emissions in industry and transport and help to store and transport renewable energy.
The future role of hydrogen will depend on dialogue and collaboration, government policies incentivizing investment in research and development, building new cross-border partnerships, removing market barriers, and encouraging new business models that make hydrogen technologies viable.
Green hydrogen can also be used to make other green derivatives and energy carriers such as green ammonia and e-methanol. These products could play an innovative role in decarbonizing maritime transport and fertilizers for food production. This could hasten a new sustainable and circular economy with net zero emissions.
The economics of green hydrogen will be challenging; the current cost of production is US$ 5 to US$ 6 per kg whereas the target for a viable sector is US$ 1.5 per kg. This will be achieved through reductions in renewable energy costs, improved conversion technologies for electrolyzers and deployment of digital twins to inform Original Equipment Manufacturers of the optimal designs. Investors keen on energy transition investments will find the green hydrogen industry to be a new blue ocean play.