Green hydrogen, also known as renewable hydrogen, will play a vital role in reducing global carbon emissions and help heavy industry move closer to a carbon neutral future. Global warming is one of the most serious problems the world is currently facing.
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Unless significant steps are taken to reduce carbon emissions, we will not be able to prevent climate change and its severe impact on our planet. Perhaps our biggest opportunity to reduce the world’s carbon footprint is to shift from fossil fuel sources to renewable energy sources. Green hydrogen is a form of clean energy that is likely to ease this energy transition to allow the world to move away from highly polluting non-renewable energy sources.
Global Commitment to Green Hydrogen
President Biden has committed to developing the use of green hydrogen in the US. With the goal of eventually achieving a hydrogen economy, an energy system in which power plants run on clean fuels, the President of the United States has pledged $8 billion in federal funds to hydrogen power centers. It was also announced that the US Department of Energy will invest $100 million in the research and development of hydrogen and fuel cells. Other countries have made similar commitments: The EU plans to invest $430 billion in clean hydrogen by 2030, and countries such as Chile, Japan, Germany, Saudi Arabia and Australia have also announced significant investments in this area of clean energy.
Use of green hydrogen
For green hydrogen to reach its full potential, it must be adapted for use in highly polluting industries. While the green hydrogen industry is still in its infancy, five major applications for this renewable energy source have already been developed.
Green hydrogen is being used to replace existing hydrogen feedstock. While only water is released when burning hydrogen, the hydrogen production process can be very carbon intensive. However, the hydrogen produced by green hydrogen methods is produced using renewable energy sources instead of fossil fuels.
The total stock of hydrogen in the US in 2015 was about 10 megatons and is projected to grow to 14 megatons by 2030.
Replacing this feedstock with green hydrogen offers the opportunity to significantly reduce the carbon emissions associated with the production of conventional hydrogen.
Residential and commercial heating systems
Green hydrogen is also being used to decarbonize residential and commercial heating systems, which are a major source of carbon emissions in many countries. Green hydrogen is blended with natural gas as a “quick fix” to reduce heating-related emissions. However, this is only possible with relatively high natural gas prices.
Energy storage is another key application of green hydrogen. The main application of traditional hydrogen energy is the production of fuel cells.
Currently, scientists are working on creating batteries from energy obtained from renewable energy sources through electrolysis, but the first attempts have led to a decrease in energy efficiency compared to conventional batteries.
While this major problem needs to be addressed before green hydrogen can be used for energy storage, recent studies have shown that green hydrogen for energy storage applications is cost effective when energy storage for more than 13 hours is required.
Production of alternative fuel
The fourth main application of green hydrogen is the production of alternative fuels.
Currently, the expansion of green hydrogen production for a number of applications faces a number of distribution and storage challenges. One way to solve these problems is to convert hydrogen into a less volatile and less flammable compound such as ammonia or methane. However, since energy is lost in this conversion, this approach is only suitable if the final product has a relatively high cost.
Fuel cell vehicles
Green hydrogen is used to power fuel cell vehicles. This application of green hydrogen is one of the most frequently cited ways to use renewable energy, however, green hydrogen fuel cell vehicles have not yet gained significant acceptance in the automotive market.
It is likely that in the next decade green hydrogen will be important for other applications than to replace internal combustion engines in vehicles. However, fuel cell vehicles may catch on in certain markets such as industry and manufacturing that rely on forklifts and other material handling vehicles.
Future Directions of Green Hydrogen
Green hydrogen is becoming a vital ingredient in encouraging energy transition from fossil fuels to renewables to ensure a sustainable future for the planet.
As the cost of producing green hydrogen decreases and the technology to develop it becomes more advanced, we are likely to see more applications of green hydrogen.
Blue hydrogen, for example, is one of the key offshoots of green hydrogen that could see rapid expansion in the coming years. Blue hydrogen is green hydrogen that is produced from natural gas and is increasingly being used to store energy in vehicles, as well as to heat buildings.
Links and further reading
David Baker, 2022 Biden‘Hydrogen Hub plan fuels $8 billion race among US states [online]. Bloomberg. Available at: https://www.bloomberg.com/news/articles/2022-04-08/biden-s-hydrogen-hub-plan-sparks-8-billion-race-among-us-states (last accessed in August 2022)
Li, Y. and Taghizade-Hesari, F., 2022. Economic Feasibility of Green Hydrogen and Fuel Cell Electric Vehicles for Road Transport in China. Energy policy, 160, p.112703. https://www.sciencedirect.com/science/article/pii/S0301421521005681
Perez, R., Brent, A. & Hinckley, J., 2021. Assessing the potential for clean hydrogen fuel for super heavy vehicles in New Zealand. energy, 14(9), p.2636. https://www.mdpi.com/1996-1073/14/9/2636
Orsted. [Online]. renewable hydrogen. Available at: https://orsted.co.uk/energy-solutions/renewable-hydrogen?gclid=Cj0KCQjw9ZGYBhCEARISAEUXITUN4EGG5XRFGcq_R11x1oIRKZqS3em_k0-xyAqGtu0_D-XSBEgkpM4aAuEvEALw_wcB (last accessed August 2022)