The consequences of climate change such as flood disasters, storm damage and heat waves are omnipresent. In 2015, 195 countries and the European Union committed to limiting global warming to below 2 degrees with the Paris Climate Agreement. In terms of implementation, this means that the EU wants to become CO2, i.e. climate neutral, by 2050.
Limiting warming to below 2 degrees seems too low and rather a politically motivated target. Nevertheless, it is an uphill task to achieve this goal. We are lagging behind the intermediate targets, nor has it yet fully crystallised which technologies we want to use to decarbonise society. One possible approach to achieving climate neutrality is green hydrogen. This article is dedicated to that.

Green hydrogen – the idea

Hydrogen is a colourless gas. The colour assigned to it represents the way it is produced. Grey hydrogen is already used in industry and is produced from natural gas by a process called steam reforming. Since CO2 is a waste product, it is not climate-neutral. Green is supposed to indicate that it is produced with renewable energies. For us in the north, that means mainly with wind energy. The idea is that water, not drinking water of course, because that would not be sustainable, is split into hydrogen and oxygen in an electrolysis with green electricity. The hydrogen can then be stored and used for reverse power generation when the wind is not blowing. It can also be made available to the industrial, heating and transport sectors.
Green hydrogen enables these sectors to be coupled and optimised together. In this way, all sectors can be decarbonised, joint energy storage can be created and energy can be saved.

Green hydrogen in Kiel

What role can hydrogen play in climate protection, heat supply, electricity storage, mobility and value creation in the Kiel region? The Hystarter project in Kiel investigated this question.
Value creation is important. A technology must be competitive on the market and manage without subsidies in the long term. Hystarter sees potential for the Kiel region in the production and storage of hydrogen, as well as in the settlement of technology companies. It is not enough to export hydrogen technologies. With the restructuring of the energy industry, we will open up many new business fields. Regionally, our own hydrogen industry is to be established, creating new jobs. Also due to its maritime infrastructure, the Kiel region could become a hub for the production, import, storage and onward transport of green hydrogen.
The result of the Kiel Hydrogen Project has been available as a concept since mid-2021, and the first hydrogen pilot projects will be realised in 2024 at the earliest. However, this requires further funding from the federal government.

Green hydrogen – the criticism

In principle, we could become climate-neutral with green hydrogen if there weren’t several problems:
The expansion of onshore wind energy has stalled. We do not have enough capacity in Germany to meet our demand for green hydrogen. In order to run a hydrogen economy, it must be established not only regionally, but globally. We need partners and will be dependent on imports.
Much of the original energy is lost during production, storage and transport. The efficiency is poor. Due to the high loss of energy, the goal of economic efficiency is difficult to achieve. In addition, electricity, including green electricity, is very expensive in Germany, as taxes, levies and surcharges account for more than 50 %. Unless these are drastically reduced, the production of green hydrogen will also be expensive. This can hinder the development of a hydrogen economy in Germany. Instead of benefiting from the conversion of the economy, it is possible that industry will migrate to countries where hydrogen is produced cheaply.
No country in the world is currently running a hydrogen economy. Green hydrogen is being researched intensively right now. Successful on a small scale. Whether these projects also scale up, i.e. whether they also work on a large scale, is still unclear.
Not to be neglected: Hydrogen is a highly reactive gas and has a high hazard potential.

Green hydrogen – hype or innovation

The EEG levy for the production of green hydrogen has been (partially) abolished in the EU. Although the price of renewable energies remains very high due to taxes, levies and charges, the production of green hydrogen has become cheaper. Experts expect further cost reductions in the future. In addition, fossil fuels will become more expensive due to the introduction and continuous increase of the CO2 price. This and the formulation of a national hydrogen strategy by the German government, in which it promotes green hydrogen and sees it as a key element of the energy transition, has triggered a hype about hydrogen. But will a hydrogen economy develop from this?
The possibility of producing hydrogen and using it as an energy carrier has existed for a long time. There have been no groundbreaking advances in recent decades, especially not ones that would have drastically reduced the costs of production. Due to the ambition to become climate-neutral, research projects are being massively promoted worldwide. It is hoped that learning effects will reduce costs. One of these funded projects is the innovative Karlsruhe Copernicus project P2X. There, synthetic fuel is produced that is climate-neutral. Since several steps could be combined into one, the production is very energy-efficient and has a high degree of efficiency. This hydrogen project is considered a promising candidate to make green hydrogen marketable even at a still moderate CO2 price.
Efficiency is the decisive factor. With electrification it is high, with green hydrogen it is low. Therefore, the passenger car sector already seems lost. In other sectors, too, it will be difficult for green hydrogen to establish itself as a key technology. The use of hydrogen is being tested in buses. Since electrification is possible here, Kiel seems to prefer it and has recently equipped terminal stations with a charging infrastructure. Our coastal power plant could also be converted to burn hydrogen. Instead of burning hydrogen, heat pump technology will probably be used.
In short, wherever green hydrogen is not an alternative, it will have problems gaining market acceptance because of its low efficiency. But where electrification fails, such as in aircraft and cruise and container ships, green hydrogen could become established, especially since there are hardly any alternatives at present.

Conclusion

Science has established that climate change not only exists, but is caused by humans. We will already reach a global warming of 1.5 degrees in the next few years. In order not to miss the 2 degree target, there is an urgent need for action. We must first invest massively in the expansion of renewable energies before we can think about producing green hydrogen. Only if we build up a hydrogen economy ourselves can we also profit economically from it.
Some countries consider nuclear power to be the key technology of the energy transition. Recently, the EU announced that it wants to engage in greenwashing. It wants to regard nuclear power and natural gas as sustainable and promote these technologies. Spain, like Germany, is sticking to its nuclear phase-out and wants to become climate-neutral with green hydrogen. Whether it will become a key technology in the energy transition depends on many factors, however. Not this article, but only the future will answer whether we will decarbonise our society with green hydrogen.

Text: misoki, Images, Illustration: misoki