In Germany there have been recent reports that hacking attempts on water and power suppliers have increased. It is not really surprising that such institutions are primary targets in case of a cyber-attack by foreign countries because power or water outage could lead to a very critical situation quickly. Marc Elsberg’s book Blackout describes quite well that a wide-spread blackout could be hard to recover due to to power network instabilities and thus lead to severe consequences only after a few days: shortage of medical supply, fuel, food, heating, communication and so on and thus also a raise of criminal activities due to lack of life-critical resources in many areas. Hopefully this scenario will never occur, but experts consider it a genuine risk and there have been cases like in the Ukraine in 2015 where cyber-attacks led to power outages. Not only the German government published a checklist to prepare for such situations. I agree that you should have the following basic supplies at home all the time:

• Sufficient drinking water for one week (2 liters per person and day)
• Food supply for one week (rice, pasta, cans of tinned food)
• Portable, battery-driven radio
• Flashlights
• Candles
• Spare batteries
• Camping stove
• Some way to heat at least one room
• Always sufficient fuel (in your car or a canister)

You should also be prepared that you might not be able to communicate via internet or phone and that electronic devices like a garage opener will not work in case of a power outage.