Surrounded by rolling farmland near the banks of the Inn River, the former Bierwang natural gas field in Unterreit is one of Germany’s largest underground gas storage facilities.
Managed by the German operator Uniper, Bierwang can hold more than 800 million cubic meters of gas, enough to supply the neighboring city of Munich for eight months.
Like other storage sites, Bierwang replenishes inventory between winters, to keep homes warm and Germany’s energy-hungry industry power-hungry during the cold months when demand is highest.
But this year, the stakes are higher than ever.
As the war in Ukraine rages on and Moscow is increasingly seen as an unreliable supplier, governments across Europe scramble to stockpile supplies before Moscow decides to cut gas flow or shut down the taps completely.
“Security of supply this winter will depend on two factors: how full storage facilities are and how much new gas continues to arrive” from abroad, said Sebastian Herold, professor of economics at the University. energy at the Darmstadt University of Applied Sciences.
Russian deliveries will play a “decisive role” in this, Herold said.
Efforts by successive German governments to establish closer economic ties with Moscow have left the country hooked on Russian energy imports, a policy now widely seen as misguided.
– Injected into the rock –
Fears that a sudden shortage of Russian gas could bring Europe’s biggest economy to its knees recently prompted the German government to pass legislation requiring all gas tanks in the country to be 90% full by November.
In total, the above and underground sites have sufficient capacity to cover 25% of Germany’s natural gas consumption. They act as a kind of buffer in times of tension in the gas market or if demand increases in abnormally cold weather.
As part of Western sanctions against Moscow, Germany has already agreed to phase out Russian oil and coal. But becoming independent of Russian gas will take longer – and it won’t be cheap as the war in Ukraine is sending energy prices skyrocketing.
So far, Berlin has managed to reduce the share of its natural gas supplied by Russia from 55% before the invasion to 35% now thanks to increased deliveries from countries like Norway and the Netherlands, and through liquefied natural gas (LNG) contracts.
At Bierwang, a network of long-distance gas pipelines carries the gas to the storage facility. The gas is then compressed before being injected into porous sandstone and stored in deep natural reservoirs.
This method can store large amounts of natural gas, but it takes longer to fill and empty than with a second type of underground storage that relies on large caverns in rock salt formations, more common in northern Germany.
“We’re on track to hopefully provide backup supply this winter,” said Doug Waters, managing director of Uniper Energy Storage, which operates nine storage facilities in Germany.
– Ex-Gazprom unit –
German gas storage sites were 55% full on Tuesday, according to Germany’s Federal Network Agency, which publishes daily updates online.
The current occupancy rate is “better than previous years, but still not enough,” said agency head Klaus Mueller.
The location of the important Rehden gas storage facility in the north, the largest in the country, complicates Germany’s challenge to prepare for winter.
The German state temporarily took control of the site’s owner, Gazprom Germania, in April, a move Berlin said was necessary to ensure energy security as ties with Russia deteriorated.
Berlin suspects that the unit’s former owner, Russian state-owned Gazprom, deliberately kept supplies low before the invasion of Ukraine to give it leverage over Germany.
Last month, Russia cut off supplies to Gazprom Germania in retaliation for Berlin’s decision.
The Rehden facility, with a gas storage capacity of four billion cubic meters, was only 7.95% full on Tuesday.