REUTERS - Essar
The refinery lost power around 1400 GMT on Tuesday causing all units to shut down.
"The fault was found and corrected within a few hours, and restart of the site has progressed well overnight, with boilers back on line and units being re-commissioned," spokesman Jonathan Miller said in an e-mail.
"Product stocks are good and customers are lifting at normal levels. We expect all units to be back on line within the next five to six days, with some units much sooner."
(Reporting by David Sheppard; editing by Jason Neely)