At the Siemens Gamesa factory in Aalborg, Denmark, where the next generation of offshore wind turbines is being built, workers are on their hands and knees inside a shallow, canoe-shaped pod that stretches the length of a football field. It is a mold used to produce one half of a single propeller blade. Guided by laser markings, the crew is lining the sides with panels of balsa wood.

The gargantuan blades offer a glimpse of the energy future that Europe is racing toward with sudden urgency. The invasion of Ukraine by Russia — the European Union’s largest supplier of natural gas and oil — has spurred governments to accelerate plans to reduce their dependence on climate-changing fossil fuels. Armed conflict has prompted policymaking pledges that the more distant threat of an uninhabitable planet has not.

Smoothly managing Europe’s energy switch was always going to be difficult. Now, as economies stagger back from the second year of the pandemic, Russia’s attack on Ukraine grinds on and energy prices soar, the painful trade-offs have crystallized like never before.

Moving investments away from oil, gas and coal to sustainable sources like wind and solar, limiting and taxing carbon emissions, and building a new energy infrastructure to transmit electricity are crucial to weaning Europe off fossil fuels. But they are all likely to raise costs during the transition, an extremely difficult pill for the public and politicians to swallow.