Since October, TÜV Rheinland, GVG Rhein-Erft, and RNG have been conducting tests in Erftstadt, near Cologne, Germany, to assess the impact of adding 20% hydrogen to the gas network. This experiment was carried out in compliance with German legislation, which previously allowed a hydrogen blend of up to 10%.
At the conclusion of the heating period, the partners conducted a preliminary assessment and discovered that all gas consumption devices connected to the network operated without any issues. Homeowners and businesses were able to use their devices as usual throughout the testing period, without the need for conversions or disruptions to regular gas network operations.
The field test is set to continue until the end of December, with 100 households from the Niederberg, Borr, and Friesheim districts participating. These districts were chosen for the test due to the suitability of their approximately 9 km long network, which was constructed in 2007.
TÜV Rheinland conducted the first-ever field test on an L-gas network in Germany. L-gas differs from H-gas in terms of gas composition and origin. The L-gas supplied to western Germany has a lower energy content (80-87% methane) and is more cost-effective compared to H-gas, which contains 87-99% methane and has a higher energy content and cost.
In collaboration with GVG Rhein-Erft and RNG, TÜV Rheinland introduced hydrogen into the test area in stages. Initially, a mixture of 10% hydrogen and natural gas was used, which was gradually increased to 15% after four weeks. Since October 2022, the gas network has been operating with a 20% hydrogen admixture.
“To ensure the suitability of each individual gas appliance in the project area, we subjected all gas-consuming devices in the test area to a test gas containing 23% hydrogen,” explained Mr. Michael Thys, the project manager from GVG.
TÜV Rheinland intends to expand its testing to explore the technical possibilities of a hydrogen admixture of up to 30% in suitable gas networks.