Hydrogen is regarded as the alternative energy carrier of the future. However, its transport over long distances calls for a special safety concept. Energy managers wishing to transport hydrogen in existing and new pipelines must furnish evidence of their pipeline’s service life by way of fracture mechanics. TÜV SÜD’s experts supply fracture mechanical analyses as well as readiness investigations and assessments.
Hydrogen Power Storage & Solutions (HYPOS), a hydrogen network in Central Germany, aims at leveraging the potential offered by a green hydrogen economy to ensure cost-effective implementation of climate-change and environmental-protection targets. The Zwanzig20 (Twenty20) programme, funded by the Federal Ministry of Education and Research, is designed to promote research and development (R & D) projects and also drives hydrogen technology from production to use.
Focus topics addressed by these initiatives include the new hydrogen infrastructure and the existing natural-gas infrastructure. Blending of hydrogen into natural gas pipeline networks is another aspect investigated by the initiatives. A significant factor in this context is how hydrogen affects other materials. The H2-PIMS project focuses on developing a pipeline integrity management system (PIMS) to operate natural gas lines with hydrogen-rich gases and on preparing a guide to converting existing pipelines to hydrogen transport.
When is infrastructure suitable?
Germany has a track record of changing the fluid transported in pipelines. When first installed, pipelines transported what was known as ‘town gas’ produced from coal, already containing hydrogen to a certain percentage. However, they have carried natural gas since the 1950s. In the event of a transition to hydrogen, the tried-and-tested pipeline infrastructure can also be used to transport this new form of energy, a major advantage for the managers of the German pipeline network. However, in spite of the pipeline network’s general suitability, some aspects need to be considered.
The installation and operation of energy-supply infrastructure falls under the scope of the Energy Management Act (EnWG) [3]. Applications involving a maximum permissible operating pressure exceeding 16 bar additionally fall under the scope of the High Pressure Gas Pipelines (GasHDrLtgV) [4]. The technical requirements have been defined in the standards of the German Association of the Gas and Water Industry (Deutscher Verein des Gas- und Wasserfachs e.V. (DGVW)). At present a change in fluid, which may adversely affect the pipeline, is considered a major change and necessitates notification in accordance with EnWG/GasHDrLtgV. The technical specification relevant to the conversion of an existing pipeline to hydrogen or the construction of a new pipeline are described in DVGW Worksheets G409 [6] and G463 [5].