Green hydrogen in fuel cell quality from the municipal gas grid
14 June 2025
Green hydrogen is playing an increasingly important role in the CO2-free energy supply. In a joint project, the Helmholtz Institute Erlangen-Nürnberg for Renewable Energy (HI ERN) and the Institut für Energietechnik (IfE) expanded the use of green hydrogen in the district town's gas network. The project partners investigated how isolating pure hydrogen from Stadtwerke Haßfurt's natural gas distribution network (4-5 vol% hydrogen in natural gas) could be technically advantageous and efficient. This allows an additional sustainable source of hydrogen — the municipal gas network — to be utilized, and helps balance out electricity fluctuations from renewable energy sources, such as wind power and photovoltaics.
High-purity hydrogen successfully isolated from the gas grid for the first time
The plant at the demonstration site in Hassfurt was commissioned in May of this year. It uses high-temperature HT-PEM stack technology from the Munich-based company Siqens. This technology enables the separation, compression, and temporary storage of high-purity hydrogen directly from the municipal gas network — a prerequisite for its subsequent conversion into electricity in the fuel cell.
In stationary operation, the plant can process natural gas at a rate of up to 600 liters per minute. Thus, it achieves the planned production volume of 2.4 kilograms of hydrogen per day. Additionally, stable operation was demonstrated by running a wide operating window at various process parameters. Besides converting hydrogen into electricity in a stationary fuel cell, the high-purity hydrogen can be used for chemical or industrial processes, as well as at a hydrogen filling station to refuel fuel cell vehicles.
HI ERN coordinated the project and provided scientific support. Researchers aimed to evaluate electrochemical compression as a method of isolating pure hydrogen (fuel cell quality) from a natural gas-hydrogen mixture in Stadtwerke Haßfurt's distribution network.
The project was funded by the Bavarian State Ministry of Economic Affairs, Regional Development, and Energy.
Project Background
Stadtwerke Haßfurt GmbH operates numerous renewable energy plants, several large-scale battery storage facilities, and an electrolysis plant with an electrical power consumption of 1.25 MW. Since 2016, the plant has operated using electricity from a community wind farm to supply up to 225 m³/h of hydrogen. Currently, the hydrogen is fed into the public gas grid at a rate of up to 5% by volume, and an increase to 10% by volume is planned. In 2019, the hydrogen plant was supplemented by a hydrogen cogeneration plant with a combustion engine.
Decentralized fuel cell installations are planned for the future. To support these applications, hydrogen must be made available at various locations in the city. Rather than building a dedicated hydrogen network, the existing gas network will serve as a transport system, and hydrogen will be isolated from the mixture at the point of use with sufficient purity. Therefore, the project has an immediate practical application: using the existing natural gas network to distribute and store green hydrogen could be an important building block of a future sustainable hydrogen economy.
Projekt Partners
Helmholtz Institute Erlangen-Nürnberg for Renewable Energy (HI ERN)
Institut für Energietechnik (IfE) an der Ostbayerischen Technischen Hochschule Amberg-Weiden
Stadtwerke Haßfurt GmbH
University of Rostock
Further Information
Press release Siqens (8 February 2025)
Contact
Timo Schaerfe
Team Lead "Process Design and Intensification"
Room 4011