Government tests energy blackout emergency plans as supply fears grow

Exclusive: Whitehall officials have war gamed' Programme Yarrow, a blueprint for coping with outages for up to a week

The government has war gamed" emergency plans to cope with energy blackouts lasting up to seven days in the event of a national power outage amid growing fears over security of supply this winter.

The Guardian has seen documents, marked official sensitive", which warn that in a reasonable worst-case scenario" all sectors including transport, food and water supply, communications and energy could be severely disrupted" for up to a week.