What is the Strategic Petroleum Reserve?

Prompted by a crippling oil embargo in the 1970s, the U.S. created the world’s largest oil reserve. But in a world shifting to renewables to combat climate change, its future is uncertain.

In late November 1973, the world was just beginning to feel the fallout from the Yom Kippur War, a conflict between Israel and its neighbors Egypt and Syria.

To punish the United States and other western nations for supporting Israel during the war, the Organization of Arab Petroleum Exporting Countries (OPEC) cut off oil supplies—tripling the average price of imported crude oil. By November 25, the crisis had grown so dire that then-President Richard Nixon addressed the nation, asking citizens to lower their thermostats, refrain from driving on Sundays, and go easy on their Christmas light displays.

In the years that followed, the U.S. pursued a policy of energy independence, to protect it from such crises in the future. One of the new policy’s initiatives was the creation of the Strategic Petroleum Reserve (SPR), a stockpile of crude oil that the country could tap during emergencies. With a present-day capacity of more than 727 million barrels of oil, the reserve allows the country to respond to shortages—and attempt to prevent them.

Most recently, the U.S. said it would release 30 million barrels to energy companies after Russia, one of the world’s top oil producers, once again invaded Ukraine in late February 2022. Coordinated with other world powers, the release was intended to stabilize volatile oil markets and ultimately reduce gas prices that were skyrocketing amid fears of a shortfall.

But many environmental advocates argue that relying on the Strategic Petroleum Reserve to manage shortages is only a stopgap measure. In light of the looming climate crisis, they argue, the U.S. should end its dependence on fossil fuels and pivot to green energy sources instead.

How much oil is in the Strategic Petroleum Reserve?

The Strategic Petroleum Reserve (SPR) is the world’s largest known oil reserve. It’s split across four sites along the Gulf Coast of Louisiana and Texas, chosen for their access to marine terminals and pipelines needed to move oil. The petroleum is piped deep underground for storage, into caverns carved out of salt domes which are considered to be the most environmentally secure way to store oil because of their low permeability.

As of March 4, 2022, the SPR held about 577.5 million barrels of light crude oil, which can be refined and turned into products including gasoline, diesel fuel, heating oil, and jet fuel. Although the U.S. Congress originally stipulated in 1975 that the reserve should be able to hold up to a billion barrels, that capacity has never been reached. The most oil that has ever been in the reserves—and the most its current facilities can hold—was 727 million barrels in December 2009.

For many years, the U.S. was required to maintain a certain level of oil in its reserves—equaling 90 days of net imports—to meet its obligations to the International Energy Agency. Formed in 1974 in response to the OPEC oil embargo, the IEA coordinates global oil releases among its 31 member countries during emergencies. But the U.S. no longer had to meet the reserve requirement as of 2020, when it began exporting more oil than it imported. That development was largely due to the rise of fracking—injecting high-pressure water, chemicals, and sand into shale rock deposits to get at the gas and oil trapped within them.

How does the Strategic Petroleum Reserve work?

The Strategic Petroleum Reserve was originally created for emergencies—to be used in the face of severe disruptions to the global oil supply. To date, the U.S. has only ordered three emergency releases from the reserve. In 1991, when war broke out in the Persian Gulf during Operation Desert Storm, the U.S. released 17.2 million barrels of oil. In 2005, when Hurricane Katrina devastated oil production along the Gulf Coast, 20.8 million barrels were released. And in 2011, the U.S. and IEA jointly released 60 million barrels of oil when the civil war in Libya disrupted oil supplies.

But global emergencies are not the only time the U.S. taps into its oil reserves. The U.S. also periodically conducts sales to private companies from the Strategic Petroleum Reserve to test its readiness or raise revenue. And the country can also use the reserve to help private companies recover from smaller-scale disasters, such as extreme weather or shipping channel closures.

In the wake of Hurricane Harvey in 2017, for example, the U.S. loaned 5.2 million barrels of oil to help Gulf Coast refineries continue their operations. Known as exchanges, these agreements require the private company to replace the oil that it borrowed, plus interest.

The future of the Strategic Petroleum Reserve

The Strategic Petroleum Reserve’s role may continue to evolve in the years ahead. Scott L. Montgomery, a lecturer at the University of Washington, writes that the reserve “has entered a new era” now that the U.S. is a net exporter of crude oil. As global efforts to reduce carbon emissions slow the demand for oil, he notes that it’s not clear how urgently the country needs an emergency supply.

But the U.S. is not expected to remain a net exporter forever, and advocates of the Strategic Petroleum Reserve say that there is value in maintaining a stockpile to help weather everything from rising oil prices to wars and unrest across the globe. As the world teeters on the edge of an energy crisis, they argue it may be more necessary than ever.

Environmental activists, however, say that the volatility of global oil markets are precisely why the U.S. should shift away from relying on the Strategic Petroleum Reserve. The U.S. consumes about 20 million barrels of crude oil per day—meaning the SPR could only last about a month if the U.S. were cut off from all other sources of oil. Rather than build up reserve capacity, they argue that the U.S. should invest in electric cars and buses and other clean energy initiatives.

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