28 March, 2023
The steel pipelines installed in the German gas grid are suitable for transporting hydrogen. They were found to possess no differences in terms of their basic suitability for transporting hydrogen compared to natural gas. Both operational ageing and the required fracture toughness and strength meet the expectations for safe availability spanning decades. This is the conclusion of the research project entitled "Random testing of steel materials for gas pipelines and systems to assess their suitability for hydrogen" (SyWeSt H2 – Stichprobenhafte Überprüfung von Stahlwerkstoffen für Gasleitungen und Anlagen zur Bewertung auf Wasserstofftauglichkeit) of the Deutscher Verein des Gas- und Wasserfaches e.V. (DVGW – German Gas and Water Industry Association). The project was conducted by Open Grid Europe and the Materials Testing Institute of the University of Stuttgart. For this research project, a representative cross-section of the steels used in German and, in some cases, European pipelines was exposed to extreme operating and ageing conditions with hydrogen, and subjected to technical tests.
“The results of the research are groundbreaking for the future of hydrogen. Of the three main challenges along the value chain - production, transportation and utilisation - transportation has now been fundamentally solved. In pipeline networks, the existing pipes can continue to be used, and only individual components or station elements need to be upgraded or replaced. It makes economic sense, as we can draw on an existing infrastructure with a total investment volume of around 300 billion euros that has been made over many decades. The German government must now utilise this great potential and pave the way for the hydrogen economy in order to live up to its claim of accelerated climate protection,” explains Prof. Gerald Linke, Chairman of the Board of the DVGW.
Rather than developing a new gas network for the transportation of hydrogen, the existing German gas grid, which is more than 550,000 km long, can be converted for the transportation of hydrogen at a total cost of approximately only 30 billion euros. Millions of households and businesses with a gas connection are already H2-ready or can be made H2-ready with relatively little outlay and effort, enabling them to be supplied with 100 percent climate-neutral hydrogen via existing infrastructure.
To ensure that this transition also has complete practical and legal certainty, the DVGW has adapted its rules and regulations for the use of up to 100 percent hydrogen and is currently in the process of supplementing these with several additional standards.
As part of the research project, samples of the types of steel used in German pipelines were subjected to exhaustive measuring methods that, in contrast to previous studies, took into account additional variables such as the influence of the hydrogen pressure. These new methods enable more accurate service life forecasts and correspondingly longer predictable operating times for pipelines, which at the same time allows for improved planning and maintenance of the gas network.