In Erftstadt, a city near Cologne, grid energy provider GVG Rhein-Erft and distribution operator RNG are currently testing the effects of blending 20 volume percent hydrogen in the natural gas network there. The interim results of the field test running since October 2022 are thoroughly positive. All of the connected gas consuming installations, according to independent test organization TÜV Rheinland, are running 100 percent problem-free. Citizens as well as the businesses connected were able to use their devices like usual throughout the whole heating season. The consuming devices did not need to be altered in order to use the gas blend. The gas tightness of the network was unaffected.

Up to now, only a blending of 10 vol.% hydrogen has been allowed for the German gas grid. The test confirms that “both the gas network and the connected gas consuming installations can tolerate twice that amount of hydrogen blending,” as stated by Reiner Verbert, project manager at TÜV Rheinland. This test is the first to be carried out in a low calorific gas grid in Germany. The field test is to run until the end of December of this year. A total of 100 households from the city regions of Niederberg, Borr and Friesheim are taking part in it.

The area is particularly well suited for this pilot run important for the energy transition because the network of about nine kilometers (6 miles) was only just built in 2007 – so the technical state is very modern. The distribution lines and house connections are also easy to monitor. Both the network topology and device technology of the test households are therefore especially suited to provide informative results before transferring this innovative system to other areas of the country.

Author: Niels Hendrik Petersen