It wasn’t even two years ago that everything revolved around natural gas in a remote area in the community of Unterreit in the Mühldorf district. When Bavaria’s Prime Minister Markus Söder (CSU) and Economics Minister Hubert Aiwanger (FW) appeared in front of the cameras and microphones here in May 2022, the Russian attack on Ukraine was just three months ago and the filling level of the Bierwang gas storage facility located deep beneath their feet was low was 28 percent. Since then, the second winter has already come to an end and all German gas storage facilities are still more than two-thirds full. Nevertheless, the era of natural gas should end as soon as possible, including at the Bierwang storage facility.
That’s why an experiment has been running here since the summer to see whether hydrogen can be stored in the porous rock at depth instead. At least Aiwanger has announced that he will be in Unterreit again this Tuesday to find out about the first results. “I am pleased that the tests have gone well so far,” said Aiwanger during the visit. “The goal is that, in the long term, hydrogen can be stored seasonally and then made available regardless of the weather and as needed.”
However, this experiment will not work without natural gas for the time being. Because the hydrogen, which is much more volatile with its small and light molecules, is not pressed into the ground in Bierwang in its pure form, but rather as an admixture to the usual carbon-containing natural gas. The technicians have decided to increase the proportion of hydrogen from five to ten to 25 percent. The mixture is stored in a former, long-exploited natural gas field – just like the natural gas stored here since 1975, but from its own drilling site and in its own layer, geologically separated from the natural gas storage.
For Aiwanger, hydrogen is one of his favorite energy policy topics anyway – also as a fuel for cars, although the industry has long since largely committed itself to e-mobility. But the chemical industry in the nearby Bavarian Chemical Triangle, for example, will need large amounts of hydrogen and corresponding storage in order to be able to do without fossil raw materials for its products in the medium term.
And the energy company Uniper, which suddenly found itself without Russian natural gas as a result of the war in Ukraine, had to be saved from collapse with tax money and is now practically entirely owned by the federal government, has declared that it wants to be CO₂ neutral by 2040. Uniper operates the Bierwang gas storage facility and leads the international consortium of several companies that is now testing the storage of hydrogen there. It remains to be seen whether and when so-called pore storage devices such as Bierwang will be able to be used on a large scale.