All domestic flights in Australia will be affected by the power outage at Sydney airport’s T2 terminal, leaving many passengers stranded.

A power outage at Sydney airport will affect Australian domestic flights into the weekend and has left thousands of passengers stranded and uncertain.

Passengers have had school holiday plans thwarted with flights delayed until Saturday or Sunday and others unsure when they’ll get back home or where they’re going to stay.

An air traffic controller believes there’ll be a knock-on across the country.

The backlog “is going to be bad – all domestic flights,” the air traffic controller, who did not wish to be named, told AAP.

“A couple hours of backlog will certainly bugger things up.”

The outage at terminal two on Friday caused delays at check-in and screening for passengers on airlines including JetStar, Virgin, Rex and Tiger, all of whom were playing catch-up in the evening.

Virgin cancelled 25 flights affecting 4000 passengers and Jetstar cancelled 10.

The delays were so serious Virgin Australia advised passengers to avoid the airport.

Tiger cancelled six flights and said affected customers would be offered a refund. Rex avoided cancellations but its passengers were experiencing delays of up to two hours.

Power was restored at terminal two about noon on Friday after it was brought to a standstill just after 8.30am.

“Sydney Airport has identified an issue with a substation, which caused the power interruption and affected back-up power sources,” a staff member said in a statement.

After a week in Sydney, Sunshine Coast husband and wife Marie and Greg Organ were stuck, trying to make it home for work on Saturday.

Ms Organ wasn’t impressed with the way Jetstar was treating its passengers.

“They didn’t even bother letting us know that planes were cancelled or anything,” she told AAP.

They’ve been told they’ll be put onto a flight leaving Sydney on Sunday.

“Every carrier is trying to push their flights until tomorrow or the next day,” said Mr Organ, who had been waiting on the phone for about an hour to speak to a Jetstar representative.

The South Sydney NRL team was caught up in the drama, with the Rabbitohs due to fly to Townsville for Saturday night’s match against North Queensland.

“Great day to be stuck at #sydairport #torture,” (South Sydney) Queensland superstar Greg Inglis tweeted.

Ash Druery, whose Jetstar flight home to Hamilton Island was cancelled, said he was frustrated he wouldn’t make it back for work on Saturday.

But the 32-year-old wasn’t angry about the situation.

“They’ve got 20,000 people trying to go on holidays and go home so they’re doing what they can,” he told AAP.

“It’s just a waiting game … I’ve got no control over it.”

Like many others at the airport, he’s been given a flight but has nowhere to stay on Friday night.

“I’m not going into the city. It’ll cost me 20 bucks to get in there and then 200 (dollars) at the cheapest for a room.”

He was waiting for Jetstar to call him back, hoping they would arrange accommodation.

The debacle comes on the day NSW school holidays start.

Passengers are being advised to check airline websites for flight information.