Marathon Galveston Bay, Valero Texas City Refineries Hit by Power Outage on Friday

Marathon Petroleum Corp's 593,000 barrel-per-day (bpd) Galveston Bay Refinery and Valero Energy Corp's 225,000-bpd Texas City Refinery were knocked out of production on Friday by a citywide power outage, according to the Texas City emergency management department.

The power failure in the refining and chemical production hub of Texas City comes as the U.S. Gulf Coast enters a second night of freezing temperatures because of an Arctic cold front that swept across the central, southern and eastern parts of the United States this week.

Marathon Petroleum spokesperson Jamal Kheiry said flaring became necessary at the refinery at about 6:30 p.m. CST on Friday (0030 Saturday GMT).

"Flares are safety systems that allow the safe combustion of materials in the event of unexpected operating conditions," Kheiry said. "There have been no injuries."

A Valero spokesperson did not reply to a request for comment.

Sources familiar with operations at the Galveston Bay Refinery, the nation's second largest, said the refinery shut down at about 7 p.m. on Friday.

Texas-New Mexico Power (TNMP) said on its website the outage in Texas City, located 34 miles (55 km) southeast of Houston, began at 6:21 p.m. CST.

TNMP spokesperson Eric Paul said shortly after 9 p.m. CST that it was restoring power to some customers in Texas City.

Power is expected to available to all customers in Texas City by 3 a.m. CST on Saturday.

The Galveston Bay Refinery is the second largest in the United States.

(Reporting by Erwin Seba; Editing by Leslie Adler, Jane Wardell and Kim Coghill)