An airport spokesperson says Hobby was running on a backup generator while crews worked to troubleshoot the problem.
Hundreds of passengers had to go through a manual security check. That led to long lines and some frustrated passengers.
One woman told us she'd been in line for 45 minutes and still wasn't finished.
"Flight leaves at 10:55, and I still ain't made it through here. Did the bag check at 8:55," she said. "Come on, now. How much time does it take?"
The airport says the outage lasted about an hour.
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