The UK has drawn up a so-called "black sky" contingency plan to prepare for a possible nationwide collapse of energy networks. Under the plan, media outlets will be required to provide 72 hours of back-up radio transmissions, while citizens are advised to stockpile water and food.

The UK has drawn up a so-called "black sky" contingency plan to prepare for a possible nationwide collapse of energy networks. Under the plan, media outlets will be required to provide 72 hours of back-up radio transmissions, while citizens are advised to stockpile water and food.