Fichtner investigates hydrogen pipeline transport for Germany’s energy transition

In the light of the need for energy imports for decarbonization and the potential for exporting renewable energy from countries with surpluses, Fichtner was contracted by the Deutsche Gesellschaft für Internationale Zusammenarbeit (GIZ) to investigate various transport scenarios for green hydrogen. This study is intended to help identify efficient ways to close the gap between energy demand and local energy generation through imports in Germany, particularly in the Federal State of Bavaria.

It is to be expected that Germany will continue to be dependent on energy imports even in an increasingly sustainable energy future. Neither politicians nor scientists currently expect the energy required for all sectors to be generated sustainably in Germany. Imports of sustainably generated energy will therefore play a key role in decarbonizing Germany.

At the same time, countries with a high availability of renewable energies and low local energy demand possess considerable potential for exporting sustainably produced energy carriers to consumer countries such as Germany. Green hydrogen is an energy carrier that can close the gap between producer and consumer, as it is easy to store and transport.

PIPELINE TRANSPORT OF GASEOUS HYDROGEN

Hydrogen can be transported from one place to another in different ways and in different forms. Pipelines, ships, trains or trailers are suitable for this, depending on the application.

As a project manager in Fichtner’s hydrogen department, I regularly deal with large-scale transport, distribution and storage technologies. A recurring topic in this context is pipeline transport and the repurposing or new-build of pipeline transport systems. In many cases, pipeline transport of hydrogen is the most cost-effective and efficient large-scale transport option for hydrogen, which can foster decarbonization of the energy market in a fast manner due to existing transregional infrastructures.

In this context, my colleagues and I were engaged by GIZ to conduct a study on hydrogen pipeline transport between the North African country of Tunisia, with its abundant potential for generating renewable energy, and the German Federal State of Bavaria. The study was financed by the German Federal Ministry for Economic Cooperation and Development (BMZ) and the Bavarian State Chancellery as part of the German Government and Federal States Program.

It focused on investigating three transport scenarios:

  1. Blending hydrogen into the existing transregional natural gas transmission system between Tunisia and Germany
  2. Repurposing existing natural gas transmission infrastructure for the transport of pure hydrogen (i.e. not as an admixture to natural gas)
  3. New-build of pipeline infrastructure for the transport of pure hydrogen

In addition to assessing technical aspects of gas pipeline transport along with economic viability aspects, the regulatory framework and potential production volumes in Tunisia as well as potential offtake volumes in the target region of Bavaria, our focus was on the local conditions in Tunisia. To assess those conditions, I visited Tunisia with my colleague Timo Haasch for several days to gain valuable insights from relevant stakeholders in the Tunisian energy economy.

NATURAL GAS INFRASTRUCTURE BETWEEN NORTH AFRICA AND EUROPE CONSTITUTES AN ESTABLISHED ENERGY TRANSPORT CORRIDOR

Looking at the map and the existing transmission pipelines for natural gas, it becomes clear that Tunisia, like other North African countries, has considerable geographical and technical advantages in comparison to other countries. Since the 1980s, for example, several parallel offshore gas pipelines have connected the Tunisian coastal town of El Haouaria to the Italian Mediterranean island of Sicily. This enables large quantities of Algerian natural gas to be exported cost-effectively by pipeline from the gas-producing regions via Tunisia to southern Europe. Tunisia plays the role of a transit country in this case because although natural gas is also produced in Tunisia, it is not transported on to Europe.

To put the transported volume of natural gas into perspective: The volume of natural gas supplied to Europe in 2022 via the connection between Tunisia and Sicily described above was equivalent to around a quarter of Germany’s annual natural gas demand in the same year. The compressor stations in El Haouaria, which compress the natural gas to the required pipeline pressure before it leaves the African mainland in order to ensure techno-economically viable transport through the sea to Europe, are suitably large in scale.

PIPELINE TRANSPORT OF PURE HYDROGEN IS ECONOMICALLY ATTRACTIVE

As is typically the case, it became clear that even with these large volumes of natural gas, only relatively small quantities of hydrogen could be transported in the form of a natural gas admixture. This is due to the allowed limits for hydrogen blending rates in the European natural gas transmission system, which are considerably low and are expected to remain so in the future. Accordingly, the hydrogen transport potential in such a scenario is comparatively of low magnitude. At the moment, people are mainly thinking in very large dimensions when it comes to hydrogen, so this transport alternative appears to be a rather unlikely scenario for the long-term import of hydrogen from Tunisia.

To cover the high anticipated future demand for hydrogen in the target region of Bavaria – and also in view of Tunisia’s presumably ambitious export targets – the transport of pure hydrogen represents the most attractive scenario, both technically and economically. Above all, the fact that an infrastructure for gas pipeline transport already exists can represent a major opportunity for rapid and financially attractive implementation. This is not limited to Tunisia, but applies to all countries in which pipeline sections of a potential transport route are located.

As part of the opening of a Tunisian-Bavarian hydrogen hub in Tunisia’s capital Tunis, we were given the opportunity to present the results of the study to a broad audience and discuss them with representatives of many different stakeholder groups.

Hydrogen hub opening event in Tunis

THE OPTION OF PURE HYDROGEN TRANSPORT FROM TUNISIA TO BAVARIA IS ALREADY BEING PURSUED

Infrastructure operators in Italy, Austria and Bavaria, as well as potential producers and offtakers, are already considering the transport of pure hydrogen, and letters of intent have been signed. Under the name “SoutH2 Corridor”, a pipeline corridor over 3,000 km long between Tunisia and Bavaria, via Italy and Austria, is to go into operation by 2030 to import up to 4 million tons of hydrogen per year from North Africa to Europe. About 70% of the pipelines are to be based on former natural gas transmission pipelines.

Due to its geographical proximity and many years of experience in natural gas pipeline transport to Europe, Tunisia therefore has the potential to play a key role in both the development of a comprehensive local hydrogen economy and a strong transregional energy partnership between Africa and Europe. The next few years will show what concrete steps will be taken to implement the highly ambitious plans from all sides along the hydrogen value chain. We look forward to using the experience gained from this project to further assist in shaping the development of hydrogen transport infrastructure not only between Tunisia and Bavaria, but also worldwide.