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U.S. surprises with 5 million barrel from crude oil reserve sale

Barricades protect the entrance to the U.S. Department of Energy's Stategic Petroleum Reserve in Bryan Mound, Texas May 20, 2008. REUTERS/Donna W. Carson

WASHINGTON (Reuters) - The U.S. Department of Energy will sell up to 5 million barrels of crude oil from the Strategic Petroleum Reserve, a move it said was to test the capabilities of the nation's emergency stockpile in a rapidly changing oil market.

In the first sale from the reserve since 1990 that is specifically designed as a test, the department will offer sour crude from its West Hackberry and Big Hill sites on the U.S. Gulf coast, with bids due March 14.

Surging U.S. shale oil production has changed the logistics of U.S. crude markets. Instead of moving oil from the Gulf up to the center of the country, as was traditionally the case, major pipelines have reversed course to move a glut of shale oil from places like North Dakota to points south.

"Due to the recent dramatic increase in domestic crude oil production, significant changes in the system have occurred," department spokesman Bill Gibbons said.

The test sale was needed to "appropriately assess the systems capabilities in the event of a disruption," he added.

The DOE said the test had been discussed for months internally and was timed so refineries interested in buying from the reserve can plan for when their facilities come out of annual maintenance cycles and crude oil stocks are needed in preparation for the switch over to summer grade gasoline.

The release would be equivalent to about one-quarter of the crude oil used in the United States every day, but the news still helped to push oil prices toward one-month lows.

The most recent emergency sale from the reserve was in 2011, in response to the civil war in Libya, when the Energy Department authorized a tap of 30 million barrels in coordination with the EU, which tapped a similar amount from its reserves.

(Reporting by Valerie Volcovici, Ayesha Rascoe and Timothy Gardner; editing by Ros Krasny and Bill Trott)