What is an example of hydrogen

Interesting facts about green hydrogen

1. Why is the federal government investing in green hydrogen?

Green hydrogen is central to achieving the Paris climate protection goals: With its help, it is possible to transform Germany's largest greenhouse gas producer in a climate-friendly way and at the same time to strengthen Germany as a technology location.

  • The most important area of ​​application is industry: Green hydrogen can be used as an alternative fuel to fire up stoves or together with CO2 e.g. as a building block of polymers help to replace the fossil raw material base of the chemical industry.
  • Thanks to fuel cells, green hydrogen can be converted into electricity and heat. Fluctuations in the power grid can be compensated for, houses can be heated and supplied with electricity, and vehicles can be powered.
  • Green hydrogen can be used as a fuel in traffic - especially where electrification is not useful or possible. Together with CO2 it can also be converted into other climate-friendly fuels that power trucks, ships and planes.

2. How does green hydrogen differ from blue, gray and turquoise?

In general, hydrogen is always a colorless gas. However, depending on its origin, it has different colors in its name.

  • Gray hydrogen is obtained from fossil fuels. As a rule, natural gas is converted into hydrogen and carbon dioxide (CO2) split. The CO2 is then released into the atmosphere unused and thus intensifies the global greenhouse effect: The production of one ton of hydrogen produces around 10 tons of CO2.
  • Blue hydrogen is gray hydrogen, its CO2 However, when it is created, it is separated and stored (English: Carbon Capture and Storage, CCS). The CO generated during hydrogen production2 This way it does not get into the atmosphere and hydrogen production can be converted into CO2-be considered neutrally.
  • Green hydrogen is produced by the electrolysis of water, whereby electricity from renewable energies is used exclusively for the electrolysis. Hydrogen CO is produced regardless of the electrolysis technology chosen2-free, as the electricity used comes from 100% renewable sources and thus CO2-free is.
  • Turquoise hydrogen is hydrogen, which was produced via the thermal cracking of methane (methane pyrolysis). Instead of CO2 solid carbon is created in the process. Requirements for the CO2-Neutrality of the process is the heat supply of the high-temperature reactor from renewable energy sources, as well as the permanent binding of the carbon.

3. Why does the Federal Ministry of Research rely primarily on green hydrogen?

Only green hydrogen is really climate friendly. Because only green hydrogen can be produced without fossil raw materials. Natural gas, which is used for gray, blue or turquoise hydrogen, must be promoted. This creates considerable emissions because small amounts of methane (CH4) escape, which is about 25 times more harmful to the climate than CO2 is. In addition, there is CO during the production of hydrogen2Emissions. With conventional (gray) hydrogen, around ten tonnes of CO are released per tonne of hydrogen during the splitting of natural gas2 as a waste product. In the case of blue hydrogen, this becomes CO2 Although captured and mostly stored underground, storage involves risks, high costs and is not accepted by society in Germany.

4. What role does hydrogen play in industry?

Hydrogen can heat industrial furnaces - for example in the glass, cement and steel industries. It is also relevant for the use of exhaust gases: in the BMBF-funded Carbon2Chem project, for example, hydrogen is needed to produce fertilizer, synthetic and fuel precursors from exhaust gases. Finally, important raw materials for the chemical industry can be produced with the help of hydrogen in Power-to-X processes. This is currently happening, for example, in the BMBF-funded Rheticus project.

5. What role does green hydrogen play in transport?

Hydrogen is particularly relevant in areas in which electrification is not possible in the foreseeable future, i.e. in the areas of air, long-distance, heavy-duty and shipping traffic. With hydrogen as a raw material for synthetic fuels, these traffic areas can be redesigned in a climate-friendly way. Hydrogen fueling is also an option.

6. What role does hydrogen play in the heat supply?

Hydrogen can already be added to the existing gas network in certain quantities. The limit is currently up to ten percent. However, higher proportions are potentially also conceivable. The additional hydrogen can then be burned like natural gas and only leads to water vapor. In addition, fuel cells can be used to generate heat and electricity from hydrogen. The Kopernikus project ENSURE is currently investigating how hydrogen can be integrated into the energy network of the future.

7. How much energy is there in a ton of hydrogen?

Chemically, one ton of hydrogen contains 33,330 kilowatt hours of energy. This corresponds to the average annual electricity and energy consumption of 11 three-person households in an apartment building (without water heater). However, 100 percent of the chemical energy cannot be converted into usable energy. Depending on the usage path, some of the energy is lost on the way to the consumer.

8. How efficient is the production of green hydrogen?

In the case of water electrolysis for the production of hydrogen with renewable electricity, the efficiency is currently around 60 percent. That means: around 60 percent of the energy used for electrolysis is also bound in hydrogen. However, because there is currently massive research in the field of hydrogen production, it can be assumed that its efficiency can be increased significantly in the coming years through research and development. In addition, if the heat generated by the electrolysis is reused, much higher levels of efficiency can be achieved.

9. How expensive is the production of green hydrogen?

The exact costs cannot be foreseen at the moment. What is certain, however, is that green hydrogen becomes cheaper the cheaper it is to produce renewable electricity and the further the development of water electrolysis progresses. The BMBF-funded Kopernikus project P2X, for example, is currently achieving good results: In P2X, the proportion of the rare material iridium, which is required for water electrolysis, has been reduced by a factor of ten.

10. Where should the green hydrogen come from?

Green hydrogen can be most sensibly produced where there is enough renewable energy available to operate the water electrolysis. For this reason, the Federal Ministry of Research is relying on strategic partnerships with South and West Africa and Australia. There are excellent conditions for generating electricity from wind and sun on unused areas.

When it comes to hydrogen production in Germany, there is a need to weigh up. A simple calculation example shows why: due to the climatic differences alone, according to the Max Planck Institute for Chemical Energy Conversion, three times as much power would have to be installed in Germany as in Australia in order to be able to produce the same amount of energy. However, hydrogen production in Germany can help to compensate for fluctuations in the generation of renewable electricity. In addition, compared to Australia, there is no transport by sea.

11. Where should green hydrogen be used?

First of all, where there are no simpler, climate-neutral alternatives for the foreseeable future, where hydrogen is required in large quantities and where transport can therefore be organized relatively easily. Specifically, that means: first in industry. The chemical and steel industries in particular have a high demand for green hydrogen.

12. How is green hydrogen transported?

Hydrogen only becomes liquid under high pressure and is the only way to transport it. It's complicated and expensive. That is why the Kopernikus project P2X team is researching to temporarily bind hydrogen to liquids, liquid organic hydrogen carriers (LOHC), so that it can be transported more easily.

13. Why does Germany want to start producing green hydrogen even though it has no electricity "left over"?

Germany occupies a leading position worldwide in the field of technology exports. The development of pioneering hydrogen technologies for the energy transition can permanently strengthen this position and, if necessary, even expand it. Such is the idea of ​​exporting hydrogen technologies on a large scale in the future. To do this, Germany must first set up and test appropriate systems in its own country. In addition, there are areas in Germany in which own hydrogen electrolysers can be used sensibly.

The Association of German Machine and Plant Builders states that German plant builders have a world market share of more than one sixth in the electrolyser sector. The aim of the federal government is to consolidate this share through further innovations resulting from research and development. In this way, jobs are to be created and export opportunities used in this growing branch of the economy.

14. If Germany relies on green hydrogen from Africa - where should the water for production come from?

A “Hydrogen Potential Atlas” is currently being analyzed in South and West Africa to determine the local opportunities for the production and export of green hydrogen. In these regions, sea water can be used due to its proximity to the sea. This seawater will first be desalinated with the help of renewable energy and then used for hydrogen production.

15. Which projects on green hydrogen is the Federal Ministry of Research already funding?

The Kopernikus projects make the greatest contribution to the BMBF's hydrogen research. In particular, the Kopernikus project P2X researches green hydrogen from generation to transport and use. The HYPOS project consortium is also investigating the generation and use of hydrogen. The Kopernikus project ENSURE, on the other hand, analyzes how hydrogen can be integrated into the energy network of the future. The Carbon2Chem projects and the MACOR feasibility study investigate how hydrogen could make the steel industry climate-friendly. The DEPECOR, BioDME and NAMOSYN projects are dedicated to climate-friendly fuels whose production requires hydrogen. Rheticus is investigating the production of climate-friendly chemical products with the help of hydrogen.

An overview of the most important projects of the BMBF on the subject of hydrogen can be found here.