Although the situation came to a head abruptly, it’s been years in the making. Europe is in the midst of an energy transition, shutting down coal-fired electricity plants and increasing its reliance on renewables. Wind and solar are cleaner but sometimes fickle, as illustrated by the sudden drop in turbine-generated power the continent recorded last year.

Moscow’s increased leverage over its neighbors became apparent at the tail end of the last winter, an unusually cold and long one that depleted Europe’s inventories of gas just as its economies were emerging from the pandemic-induced recession. Over the summer, state-controlled Gazprom PJSC began capping flows to the continent, aggravating shortages caused by deferred maintenance at oil and gas fields in the North Sea and raising the stakes on a costly and long-delayed pipeline project championed by the Kremlin.

At the same time, countries from Japan to China were boosting their imports of liquefied natural gas (LNG) in preparation for the coming winter. All of this left Europe struggling to replenish its dwindling stockpiles during the warm months, when gas is less expensive.

Europe’s natural gas production has been in decline for years, which has left it more reliant on imports. Now, Russia stands poised to further cement its position as the bloc’s top supplier. Gazprom and its European partners have plowed $11 billion into Nord Stream 2, a 1,230-kilometer (764-mile) pipeline running beneath the Baltic Sea from Russia to Germany.

A recent bump in LNG imports from the U.S. has provided some relief, but it’s temporary at best. France needs to take several of its reactors offline for maintenance and repairs, resulting in a 30% reduction in nuclear capacity in early January, while Germany is moving ahead with plans to shut down all of its nuclear plants. With the two coldest months of winter still ahead, the fear is that Europe may run out of gas.

Storage sites are only 56% full, more than 15 percentage points below the 10-year average.

Traders are already preparing for the worst, with prices for gas delivered from spring through 2023 surging about 40% over the past month. Some say the crunch could last until 2025, when the next wave of LNG projects in the U.S. starts supplying the world market.

“It’s hard to see how decent levels of gas storage can be achieved without additional Russian exports via Nord Stream 2 or existing routes,” says Massimo Di-Odoardo, vice president for gas and LNG research at Wood Mackenzie. “2022 will be another volatile year for European gas prices.” —With Elena Mazneva, Olga Tanas, and Vanessa Dezem