OPINION: A winter of rising gas prices, culminating in Russia’s invasion of Ukraine, has reminded European leaders that energy security cannot be taken for granted.

Pessimists worry that the continent might be at risk of a 1970s-style energy shock if Russian supplies are cut off too abruptly, particularly in countries such as Germany, Slovakia and Austria, where dependence is greatest.

Idling factories are not the only topic to lose sleep over, either. Even the staunchest backers of renewables know there is a gap to fill before the world can move away from fossil fuels.