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Hydrogen economy

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A hydrogen economy describes a system where hydrogen acts as an energy carrier. This role complements electricity to help reduce greenhouse gas emissions. The primary goal is to lower emissions in areas where clean electricity is not yet efficient or affordable. By using hydrogen, society can phase out fossil fuels and help limit climate change.

2023-10-19 Clean Hydrogen Ladder 5.0
2023-10-19 Clean Hydrogen Ladder 5.0

Hydrogen production currently relies on several different methods. Most hydrogen is "gray hydrogen," which is created from natural gas through steam methane reforming (SMR). This specific process was responsible for 1.8% of global greenhouse gas emissions in 2021. To reach climate goals, experts want to replace this with low-carbon options. One option is "blue hydrogen," which uses SMR but includes carbon capture and storage. Another is "green hydrogen," which is produced through electrolysis. Electrolysis uses renewable electricity to split water into hydrogen and oxygen.

Photo praxair plant.hydrogen.infrastructure
Photo praxair plant.hydrogen.infrastructure

There are various ways to use hydrogen as a fuel. It can be used in fuel cells to produce electricity. When a fuel cell consumes hydrogen, the only emission released is water vapor. Alternatively, hydrogen can be used via combustion to generate heat. However, combustion can lead to the thermal formation of nitrogen oxides, which are harmful emissions. Hydrogen can also be combined with carbon dioxide under heat and pressure to create green methanol. This liquid fuel is easier to store than gas and can be used in large ships.

IRENA maturity of hydrogen solutions 2022
IRENA maturity of hydrogen solutions 2022

The concept of a hydrogen-based society has a long history. In 1923, the geneticist J. B. S. Haldane theorized about using wind turbines to produce hydrogen for energy storage. He wanted to solve the problem of variable renewable power output. The specific term "hydrogen economy" was later coined by John Bockris in 1970. He spoke at the General Motors Technical Center about using nuclear and solar power to support hydrogen. In 1974, the International Energy Agency (IEA) and the International Association for Hydrogen Energy (IAHE) were established to promote these ideas.

Realizing.the.Hydrogen.Economy.chart
Realizing.the.Hydrogen.Economy.chart

In 2021, global hydrogen production reached 100 million tonnes. About 43% of this was used in oil refining for a process called hydrocracking. Hydrocracking converts heavy petroleum into lighter fuels. Another 57% went to industry, mainly for making methanol and ammonia for fertilizers. Currently, over 99% of dedicated hydrogen production comes from fossil fuels. About 70% comes from steam reforming of natural gas, while 30% comes from coal gasification. Low-carbon hydrogen currently accounts for less than 1% of all production.

IRENA hydrogen leadership opportunities
IRENA hydrogen leadership opportunities

Hydrogen is particularly useful for "hard-to-decarbonize" sectors. These are heavy industries that require intense heat, such as making steel, cement, or glass. Hydrogen can also serve as an alternative to coal-derived coke in steelmaking. For transport, it is a candidate for long-haul shipping and aviation. While hydrogen fuel cell cars exist, their market is smaller than electric vehicles. By the end of 2022, only 70,200 hydrogen vehicles had been sold worldwide. This is much lower than the 26 million plug-in electric vehicles sold.

2023-10-19 Clean Hydrogen Ladder 5.0
2023-10-19 Clean Hydrogen Ladder 5.0

There are significant challenges to building this economy. Hydrogen is difficult to store and transport through pipelines. It is also highly explosive, which creates serious safety concerns. The cost of production is another major factor. The U.S. Department of Energy's Hydrogen Hotshot Initiative aims to lower green hydrogen costs to $1 per kilogram by 2031. However, the cost of electrolyzers rose by 50% between 2021 and 2024. Future costs will depend on carbon taxes, energy prices, and available raw materials.

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🖼️ Images & Media (7)
File:IRENA maturity of hydrogen solutions 2022.svg
IRENA maturity of hydrogen solutions 2022.svg
File:IRENA hydrogen leadership opportunities.png
IRENA hydrogen leadership opportunities.png
File:Realizing.the.Hydrogen.Economy.chart.gif
Realizing.the.Hydrogen.Economy.chart.gif
File:2023-10-19 Clean Hydrogen Ladder 5.0.png
2023-10-19 Clean Hydrogen Ladder 5.0.png
File:Photo praxair plant.hydrogen.infrastructure.jpg
Photo praxair plant.hydrogen.infrastructure.jpg
File:Hydrogen_Flame_Broom_Test_NASA.jpg
Hydrogen_Flame_Broom_Test_NASA.jpg
File:Brno, Autotec, Mercedes Citaro na palivové články II.jpg
Brno, Autotec, Mercedes Citaro na...
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