It is the largest publicly known emergency supply in the world; its underground tanks in Louisiana and Texas have capacity for 714 million barrels (113,500,000 m3).
The reserve is stored at four sites on the Gulf of Mexico, each located near a major center of petrochemical refining and processing.
One of the key commitments made by the treaty's signatories is to maintain oil stocks of no less than 90 days of net imports.
[22] Access to the reserve is determined by the conditions written into the 1975 Energy Policy and Conservation Act (EPCA), primarily to counter a severe supply interruption.
[citation needed] The EPCA of December 22, 1975, made it policy for the United States to establish a reserve up to 1 billion barrels (159 million m³) of petroleum.
Fill was suspended in Fiscal Year 1995 to devote budget resources to refurbishing the SPR equipment and extending the life of the complex.
On November 13, 2001, shortly after the September 11 terrorist attacks, President George W. Bush announced that the SPR would be filled, saying, "The Strategic Petroleum Reserve is an important element of our Nation's energy security.
To maximize long-term protection against oil supply disruptions, I am directing the Secretary of Energy to fill the SPR up to its 700 million barrels (110,000,000 m3) capacity.
Since the directive in 2001, the capacity of the SPR has increased by 27 million barrels (4,300,000 m3) due to natural enlargement of the salt caverns in which the reserves are stored.
Approximately 60% of the crude oil in the reserve is the less desirable sour (high sulfur content) variety.
The oil delivered to the reserve is "royalty-in-kind" oil—royalties owed to the U.S. government by operators who acquire leases on the federally owned Outer Continental Shelf in the Gulf of Mexico.
This mechanism was adopted when refilling the SPR began, and once filling is completed, revenues from the sale of future royalties will be paid into the federal treasury.
On April 25, 2006, President Bush announced a temporary halt to petroleum deposits to the SPR as part of a four-point program to alleviate high fuel prices.
[26] On January 2, 2009, after a sharp decline in fuel prices, DOE said that it would begin buying approximately 12,000,000 barrels (1,900,000 m3) of crude oil to fill the Strategic Petroleum Reserve, replenishing supplies that were sold after hurricanes Katrina and Rita in 2005.
[21] On October 20, 2014, a report by the U.S. Government Accountability Office (GAO) recommended reducing the size of the Reserve.
[27] On March 19, 2020, President Donald Trump directed the Department of Energy to fill the Strategic Petroleum Reserve to maximum capacity, when oil was priced at $24 per barrel.
[33] As a member of the International Energy Agency (IEA), the United States must stock an amount of petroleum equivalent to at least 90 days of U.S. imports.
[36] Former Secretary of Energy Samuel Bodman said that the Department would consider new facilities for refined products as part of an expansion of 1 to 1.5 billion barrels (160,000,000 to 240,000,000 m3).