The record spike in energy prices could hardly have come at a worse time for Europe’s ambitious new climate plan, with politicians just beginning to talk about how they’re going to implement the world’s most sweeping emissions-cutting strategy.

The energy crisis is threatening double-digit increases in consumer electricity bills months before the winter freeze and it’s also squeezing industrial giants. As European governments scrambled to blunt the impact on consumers — Greece promised subsidies on power bills, for example — threats of blackouts in the U.K. this past week were a vivid reminder of the fragility of energy supplies.

For the European Union, which is proposing to ban new fossil-fueled cars by 2035 and impose new costs on dirty home heating, the steep costs of such an ambitious plan will be an even tougher sell to voters already reeling from hikes in utility bills.