Hydrogen economy

People want to use a gas called hydrogen for power.

This gas can help keep our air clean. It is a good way to help the Earth.

Most hydrogen today comes from natural gas. Making it this way can release bad air. This bad air can make the Earth too warm.

We can make better hydrogen. We can use power from the wind or sun. This makes the gas very clean.

Clean hydrogen can help big ships move. It can also help big factories. It can even help make steel.

Using this gas is a big job. It is hard to move and store. But it can help our world stay healthy.

People want to use a gas called hydrogen to help the Earth.

This idea is called a hydrogen economy. It means using hydrogen to carry power. This can help stop climate change.

Most hydrogen today is called gray hydrogen. It is made from natural gas. This way of making it lets out greenhouse gases. In 2021, this made 1.8% of global emissions.

We can make cleaner versions. One way is green hydrogen. We use a process called electrolysis. This uses power from the wind or sun to split water. We can also make blue hydrogen. This uses natural gas but traps the bad gases.

Hydrogen helps in many ways. It can power big ships and planes. It can also help make steel and fertilizer.

Some people use it to make green methanol. This is a liquid fuel. It is easier to store than gas. Hydrogen is hard to move. It can also be explosive. But it can help us move away from fossil fuels.

A hydrogen economy is a way to use hydrogen as an energy carrier. This means using the gas to move power to where it is needed. It helps complement electricity to reduce greenhouse gas emissions. This is a long-term option to help limit climate change. It is most useful when cleaner solutions are not cheap or easy to use.

Scientists want to use it to phase out fossil fuels. This could help protect the Earth's atmosphere for the future.

There are different ways to make hydrogen. Most hydrogen today is called gray hydrogen. It is made from natural gas through a process called steam methane reforming. This method caused 1.8% of global greenhouse gas emissions in 2021. We can also make low-carbon hydrogen. One way is blue hydrogen, which uses steam methane reforming but adds carbon capture and storage. Another way is green hydrogen. This uses electrolysis, which means using renewable power to split water.

The idea of using hydrogen for energy is quite old. In 1923, a geneticist named J. B. S. Haldane theorized about it. He thought wind turbines could make hydrogen and oxygen for long-term storage. The actual term "hydrogen economy" was used by John Bockris in 1970. He spoke at the General Motors Technical Center. He believed hydrogen could help when fossil fuels ran out. Later, Lawrence W. Jones from the University of Michigan also wrote about it.

In 2021, the world produced 100 million tonnes of hydrogen. About 43% was used in oil refining. Another 57% was used in industry, mostly to make ammonia for fertilizers. Most hydrogen production today comes from fossil fuels. About 70% comes from steam reforming of natural gas. Another 30% comes from coal gasification, mostly in China. Low-carbon hydrogen currently makes up less than 1% of production.

Hydrogen has many important jobs in our future. It can provide the intense heat needed to make steel, cement, and glass. It is also great for long-haul transport like big ships and planes. Some people use it to make green methanol, which is a liquid fuel. This is easier to store than gas. However, hydrogen can be hard to move in pipelines. It is also highly explosive, so it must be handled carefully.

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.

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.

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.

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.

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.

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.

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.