Mariam Abu Amra’s six children panic when the sun goes down.

They are afraid of the dark, and ever since the war in Gaza began, their home is pitch-black by bedtime. The neighborhood outside is dark, too, illuminated only by cellphone screens that use up precious battery life.

The power has been out for more than one year in the Gaza Strip, and Gazans have had to make do with alternatives that fall far short of their basic needs.

“Every night is a struggle for us,” said Ms. Abu Amra, 36, who lives in Deir al Balah, in central Gaza. “Sometimes my children ask me when the electricity will be back again, but I have no answer.”

Electricity is a fundamental building block of modern life, and Gaza has had very little of it since Israel took measures to cut off its supply in the first days of the war in what it said was an effort to weaken Hamas. That yearlong blackout undergirds almost every deprivation imposed by the war, and has turned bare necessities — from functioning medical equipment to bedroom night lights — into luxuries.

“I never knew how much all the people and the families here, including myself, relied on electricity,” said Ms. Abu Amra, who now cooks over a fire and does laundry by hand before the sun sets. “I have to wake up early now so I don’t miss a single minute of daylight.”