In the Bavarian town of Hohenwart, ten households have been heating with pure hydrogen for seven months. The project partners, Energie Südbayern, Energienetze Bayern, and Thüga, are now drawing a positive interim balance of the H2Direkt project: the first heating season went smoothly, and no modifications to the existing gas network were necessary.
H2Direkt draws a balance: the first heating season with a gas network converted to 100 percent hydrogen went "smoothly," Thüga reported on May 16. According to the project partners and customers, the interim results are positive. Even at temperatures as low as minus 15 degrees Celsius, the hydrogen infrastructure and the new heaters worked as planned.
Since the end of September 2023, ten households and one commercial customer in Hohenwart have been heating with hydrogen. They receive the hydrogen through a gas distribution network previously operated with natural gas, which was converted to 100 percent hydrogen as part of H2Direkt – a first in Germany.
The project focuses on the hydrogen suitability of the existing infrastructure in the network and in basements. It has shown no difficulties in ongoing operation, said Michael Schneider, Managing Director of Energienetze Bayern.
No Adjustments to the Gas Network Necessary
In September 2023, the newly built hydrogen feed-in plant started operations. Within a few days, the network, the connected households, and the unnamed commercial customer were switched from natural gas to hydrogen supply. No modifications were necessary in the network area – all existing components were thus suitable for hydrogen.
The heaters, on the other hand, were replaced by 100% hydrogen condensing boilers from Vaillant, and the gas meters were exchanged. During the regular inspection of all lines and infrastructure components in the network and in basements, no leaks were detected, according to Thüga. The involved customers are regularly asked for feedback and have been "very satisfied" so far.
Transferable Results
Fundamentally, the operation of the network with hydrogen hardly differs from the operation with natural gas; the odorant THT can also be used in the same way. The capacity of the distribution network is suitable for hydrogen transport despite its higher flow velocity.
H2Direkt is funded as part of the flagship project TransHyDE with funds from the Federal Ministry of Education and Research (BMBF). TransHyDE evaluates and tests hydrogen transport solutions.
