Part 1: Hydrogen as a solution to the energy transition?

Hydrogen is often seen as a key factor in the energy transition away from fossil fuels and towards climate-neutral energy sources. In principle, it can be used to do everything for which we have mainly used coal, oil and natural gas to date - without releasing CO2 when converting it back into energy. Hydrogen could play an increasingly important role in heating buildings, the transport sector and industry in particular. However, it is energy-intensive and costly to implement - and therefore not very efficient.

What is hydrogen?

It is a naturally occurring chemical element (H) that is found in water (H2O), for example, and is gaseous at normal temperature.

"Although it is the lightest of all chemical elements, hydrogen makes up around 75 percent of the mass of the entire universe and is found in all living organisms. However, hydrogen is usually found bound, as a component of larger organic compounds, and in order to make it usable as an energy carrier, it must first be dissolved using energy-intensive chemical processes." reports Quarks.

To produce it, water must be broken down into oxygen and hydrogen using electrolysis. This requires electricity. If this is obtained from purely renewable sources, it is green hydrogen .

Where should hydrogen be used?

We can use it to heat our homes, generate electricity in fuel cells and produce synthetic fuel for our cars.

It can also be used to obtain raw materials for the chemical industry, which can then be used to produce plastics, among other things. Or it could replace coal in steel production.

Another area of application is gas-fired power plants, which are to be operated with climate-neutral gases such as hydrogen in the future.

In the transportation sector, hydrogen also offers solutions for climate-friendly transport in areas where the use of electric drives is not practical or possible.

Hydrogen is also an important storage medium for renewable energies. The weather-independent availability of renewable energies is a key challenge for a climate-neutral energy supply.

How hydrogen is to be transported

There are two ways of getting it to where it is needed: by ship or by pipeline. Physicist Tabea Arndt from the Karlsruhe Institute of Technology (KIT) and her team are researching precisely this issue. Her vision: "A special development at our institute is a hybrid energy transmission line that can transport electrical energy and liquid hydrogen," she describes. "This is particularly helpful if you have a consumer, for example an airport, that needs liquid hydrogen but also electrical energy, so that you can use the same route for both."

However, the liquefaction of hydrogen itself is also very energy-intensive because it has to be cooled considerably.

Cooperation with other countries necessary

In June 2020, the German government published the National Hydrogen Strategy adopted. The aim is to use hydrogen technology to reduce CO2 emissions in the industrial, transport and energy sectors.

According to expert estimates, Germany can produce a maximum of one fifth of its hydrogen requirements itself in the long term. The majority is likely to be produced where the conditions for wind and solar are favorable. "As an industrialized nation, Germany will probably never be able to supply itself with green energy. This means that we will remain an import nation for primary energy sources and therefore also an import nation for green hydrogen," says physics professor Tabea Arndt, who researches hydrogen technologies.

"The German government therefore relies on international cooperation. Strategic partnerships with South and West Africa as well as Australia are the cornerstone for the future supply of hydrogen. In these countries, the conditions are particularly suitable for producing wind and solar power for the production of hydrogen." can be read on the German government's website.

Critical voices on the hydrogen strategy

There are many skeptical voices about the hype surrounding hydrogen. While some see hydrogen as a key element of the energy transition,

Michael Grytz and Laura-Charlotte Costan, ARD Studio Brussels, write: "In order to produce hydrogen on a large scale, an enormous number of electrolysers are needed to split water into its components hydrogen and oxygen. And an enormous number of companies are needed to produce these electrolysers. Electrolysis, in turn, requires large amounts of green energy from wind and solar power. Then you need the necessary infrastructure to transport the hydrogen to the customers, such as pipelines and filling stations."

"Hydrogen is a scarce and expensive energy source, making it the 'champagne' of the energy transition," explains Claudia Kemfert, energy economist at the German Institute for Economic Research and member of the German Advisory Council on the Environment.

Prof. Dr. Enno Wagner, Professor of Mechatronic Design and Technical Mechanics at the Frankfurt University of Applied Sciences (Frankfurt UAS), is calling for more realism on the subject. "The rethink for a sustainable energy transition will be much more drastic than some political and economic decision-makers are currently talking up. We are facing the greatest technological challenge since the beginning of industrialization. It is about nothing less than the complete restructuring of the entire global industrial machinery."

Find out more in our part 2!