Green hydrogen produced from renewable energy sources could replace natural (hydrocarbon) gas in Germany’s existing gas distribution system, says the Fraunhofer Society. It has drawn up a roadmap to a hydrogen economy and presented it to the Federal Government, which is currently working on a National Hydrogen Strategy.

In a pilot project which forms part of the positioning paper, the Fraunhofer Institute for Solar Energy Systems (ISE) in Freiberg constructed a modular hydrogen injection system and started feeding H2 into the local gas network. At the heart of it is an electrolyser with a connection power of 120 kW and a small hydrogen storage unit, which enables intermittent decoupling from the grid and gas network, so the power supply would not be interrupted.

The pilot known as the Freiburg Municipal Energy Association will serve as a research platform to test new components, operational strategies and innovations under real conditions, and to optimise the use of H2 storage, feed-in capacity and purchase of cheap surplus and renewably-sourced electricity. It is supported by Baden-Württemberg’s State Ministry for the Environment, Climate and Energy Economy.

Fraunhofer ISE worked with the Fraunhofer Institute for Systems and Innovation Research (ISI) on the hydrogen roadmap, which also involved the Institutes for Microstructure of Materials and Systems (IMWS) and for Ceramic Technologies and Systems (IKTS). It charts the various pathways for the introduction of hydrogen power into various applications and sectors. Electrolysis will be the core technology used in industry and for the production of H2 for the export market, as well as playing a flexible role in the national power grid. It is estimated that the electrolysis capacity will grow to 50 to 80 GW by 2050.

To achieve this, there is much work to be done, particularly from a regulatory standpoint to stimulate sector coupling and the production of fuel cell vehicles. Not least, there needs to be an international harmonisation of standards around the H2 economy.

There will be a substantial opportunity for German manufacturers of electrolysis systems and fuel cells to supply the growing global demand for hydrogen power, which has been estimated at around EUR 32 billion.