Lack of fuel from Israel brought Gaza's lone power plant to a halt on Friday, days after it was fired back to life following a seven-week shutdown, the electricity company said.
"The plant stopped working on Friday morning due to a lack of fuel caused by Israel's closure of the Kerem Shalom crossing," said a company official.
Israel closed the crossing to the besieged Palestinian territory on Tuesday following a series of violent cross-border incidents earlier in the week.
According to the official, the closure of the power station means that electricity supplies to Gaza would be limited to six hours a day as opposed to the usual 12 hours a day.
The plant, which supplies some 30 percent of Gaza's electricity needs, had previously fallen silent on November 1 as stocks of diesel ran out.
The power station returned to life on December 15 after receiving a delivery of fuel purchased from Israel by the West Bank-based Palestinian Authority using funds donated by Qatar.
The PA helped facilitate the delivery via Israel, which the militant Hamas does not recognise.
The Kerem Shalom crossing was closed on Tuesday following a series of cross-border exchanges between Israel and Gaza militants after the fatal shooting of an Israeli man engaged in maintenance work on the northern Israel-Gaza border fence by a Palestinian sniper.