Hydrogen should play a key role in the energy and climate transition. But how is that supposed to work? As early as 2020, the then federal government formulated a political framework for action, the “National Hydrogen Strategy” (NWS). As agreed in the coalition agreement, the traffic light coalition has now developed an update. It is to be adopted by the federal cabinet on Wednesday. An overview of hydrogen.
Why is hydrogen seen as a beacon of hope?
Because the combustion with oxygen simply produces water, i.e. H2O, and not the climate-damaging greenhouse gas carbon dioxide (CO2), as is the case with the combustion of fossil fuels. If hydrogen is produced in a climate-friendly manner, it should help to significantly reduce CO2 emissions and, according to the federal government, even “go to zero”.
Where should hydrogen be used?
Hydrogen produced with green electricity is to be used as a chemical raw material. Hydrogen has long been used as a raw material for the chemical industry, for example to produce ammonia, a starting point for fertilizers. In the steel industry, for example, eco-hydrogen is set to play a central role in the future: Where coal used to remove the oxygen from the iron ore in the production of pig iron, hydrogen is to be used in the future.
On the other hand, it should serve as an energy carrier and thus also as an energy store. In a few years, for example, it will be used as a fuel in modern gas-fired power plants to generate electricity. They are to be used when there is not enough renewable electricity available, for example from wind and solar energy. Hydrogen has long been used in fuel cells to generate electricity. Hydrogen is to be stored in former natural gas storage facilities, for example.
How is the hydrogen to be produced?
The hydrogen should preferably be produced with the help of renewable electricity in so-called electrolysis processes. Electricity breaks down water molecules into its components, oxygen and hydrogen. If electricity from regenerative energy sources is used, the hydrogen is called “green”. However, the gas is not colored.
Depending on the type of production, other colors are also used for designation. For example, one speaks of “grey” hydrogen when the greenhouse gas carbon dioxide (CO2) escapes during production from natural gas. If the released carbon dioxide is stored, it is referred to as “blue”. If solid carbon is obtained, the hydrogen is called “turquoise”.
Where does the hydrogen come from so far?
In Germany, around 55 terawatt hours of hydrogen are consumed every year, mainly by the chemical industry. So far, it has been obtained primarily from methane, the main component of fossil natural gas.
How much hydrogen will be needed in the future?
Much more than before. The previous NWS assumed a total hydrogen requirement of 90 to 110 terawatt hours for 2030. In the latest draft of the NWS update, this range has been increased: to 95 to 130 terawatt hours. To compare the amount of energy: According to the energy industry association BDEW, renewable energy sources in Germany generated around 257 terawatt hours gross of electricity in 2022.
How much is a terawatt hour of hydrogen?
A terawatt hour of hydrogen weighs about 30,000 tons. To classify: Germany’s largest steel producer Thyssenkrupp wants to put a new plant for pig iron production into operation in Duisburg in 2026, which will first be operated with natural gas and then with more and more hydrogen. From 2029, production will then run entirely with hydrogen, thereby significantly reducing greenhouse gas emissions during steel production. An annual consumption of around 143,000 tons of hydrogen is estimated.
Thyssenkrupp wants to purchase the gas for its new plant from several suppliers. It has been said that a delivery infrastructure has been in the works for several years. By 2027, the plant should be connected to a national hydrogen network.
Where will the hydrogen come from in the future?
Numerous electrolysis plants are to be built in Germany, which will primarily produce green hydrogen. If the previous NWS still assumed five gigawatts of domestic electrolysis capacity in 2030, according to the draft it should now be at least ten gigawatts. However, the hydrogen produced by these plants is unlikely to be sufficient to meet demand. The draft assumes that by 2030 around 50 to 70 percent of the hydrogen consumed will have to be imported. The hydrogen is to come to Germany primarily bound in ammonia by ship, and then also via pipelines after 2030.
What does “10 gigawatts of electrolysis capacity” mean?
The 10 gigawatts refer to the added electrical connected load of the electrolysers, whose individual capacity is usually given in megawatts. 10 gigawatts equals 10,000 megawatts. If the output of a single electrolyser is 10 megawatts, 1,000 such systems would be needed in Germany in 2030 to achieve the planned 10,000 megawatts. In February 2023, around 8.1 gigawatts of electrolysis capacity were planned in Germany by 2030, according to the H2 balance sheet of the energy company Eon.
How much hydrogen can an electrolyser produce?
That depends on the size, efficiency and operating time of the system. The electrolysis process also plays a role. An example: According to the company, the standard module of the Thyssenkrupp hydrogen subsidiary Nucera with an output of 20 megawatts can produce a maximum of 3100 tons of hydrogen per year. The market for electrolysers has grown in recent years: A market overview by the Bavarian energy network Carmen from mid-July now lists 97 electrolysers from 19 manufacturers.
