June 3 (Bloomberg) -- Motiva Enterprises LLC, a joint venture of Royal Dutch Shell Plc and Saudi Arabia's state oil company, said it expects its Port Arthur, Texas, refinery to return to full production capacity in the ``next couple of days.''

Power to the refinery, Motiva's largest in the U.S., has been ``reestablished'' since a blackout at 11 a.m. yesterday caused the plant to shut down, Stan Mays, a Shell spokesman, said in an e-mail late yesterday.

``Products will continue to be supplied from inventory that is on hand,'' he said.

The power disruption was caused by an internal electrical system malfunction, he said. Five workers taken to a hospital for symptoms including heat exhaustion have been released.

The Motiva plant has a capacity of 300,000 barrels a day, according to the U.S. Energy Department.

To contact the reporter on this story: Robert Tuttle in New York at rtuttle@bloomberg.net

Last Updated: June 3, 2008 08:56 EDT