Flights to Tenerife, Belfast and Milan were among 87 cancelled, while others were delayed by hours, BBC News reports.
Many passengers reported being stuck on grounded aircraft.
The airport said the problem was caused by a power issue affecting fuel supply.
It said in an update early this morning (20 May): “Most scheduled flights will operate as planned today, however we expect that there will be a small number of delays and cancellations as a result of the issues experienced yesterday.
“Please check the status of your flight with your airline. We apologise for any inconvenience caused and thank you for your patience.”