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March 7, 2011

Libyan supply disruption may have both direct and indirect effects

map of Libya, as described in the article text
Source: U.S. Energy Information Administration

Since the outbreak of civil unrest in Libya in mid-February, oil and gas production in that country have fallen by an estimated 60 to 90 percent. While Libya accounts for only about 2 percent of global supply, the market impact of such a supply disruption can go beyond volumetric loss. Read more about some of the key factors here. (Article also published in This Week in Petroleum, March 2, 2011.)

Crude volume versus crude quality
Although oil is generally seen as fungible, in fact, crude comes in many different grades of varying qualities and product yields. Libya's importance to the oil market stems not only from its substantial production, but also from the light, sweet quality of its crude grades. Es Sider, its largest stream, has a slightly lower gravity than benchmark grades Brent and West Texas Intermediate (WTI), (meaning that it is a slightly heavier grade of crude) but a slightly lower sulfur content (meaning that it is sweeter). Another Libyan grade, Sirtica, is lighter than Brent and WTI. Light crudes are, generally speaking, the easiest to process and can be run by relatively "simple" refineries that may not be able to handle heavier or sourer substitutes. A loss of light, sweet crude volumes is, as a rule of thumb, more difficult to deal with than a loss of heavier and sourer ones. This is not only because the refineries that run light, sweet grades have limited feedstock flexibility, but also because most of the spare crude production capacity tends to be at the heavy, sour end of the barrel. Fortunately, current utilization rates for U.S. refineries suggest that there is a significant margin of spare capacity at "complex" refineries that could be used to process heavy, sour crude oil.

Market outlet and destination
Although the majority of Libya's oil output and most of its natural gas production goes to Europe, its crude market reach is wider, extending all the way to China. But the ultimate impact of any crude disruption goes beyond the immediate buyers of that specific oil. As buyers find substitute supplies for the disrupted oil, those replacement barrels, in turn, are diverted from their original use or destination, causing secondary impacts. Should it be prolonged, a disruption in Libyan exports could have a larger effect on U.S. oil supply sources than the relatively small volumes of Libyan crude actually imported into the United States would suggest. Unlike Libyan production, more than a third of Algeria's light, sweet crude (a possible substitute from fields relatively close to Libya's) is shipped to U.S. refiners, which sometimes use it as a blending stock to lighten heavier crude grades. Should those volumes find a stronger market in Europe, U.S. end-users would have to look for alternate supplies. Light, sweet Nigerian crude, which depending on market conditions can wind up in the United States, Europe or Asia, is another case in point. Global crude oil flows will tend to adjust to best match demand needs with available supply sources.

Short haul versus long haul
Location is another important factor affecting the impact of a disruption. The closer the fields where a disruption is occurring are to their market outlet, the more immediate the disruption's impact on oil inventories and prices is likely to be, unless an alternate supply source equally close to market can be found. In December 2002 and early 2003, a worker strike that curtailed Venezuelan production was immediately felt in the United States, a short-haul destination. Substitute imports from distant Saudi Arabia took weeks to arrive. The rerouting of supplies increased shipping distances, tying up tankers for longer voyages and further tightening a shipping market that had already been firming even before the event. In contrast, while there can be indirect effects on long haul markets from localized substitution, those long haul effects would be comparatively subdued.

Crude versus products
Another way in which a disruption in one market sends ripples through others is via the product markets. Much of the Libyan crude oil refined in Mediterranean refineries is re-exported as product after processing by export-oriented refineries. Italy is Libya's top crude oil customer, with Libyan crude oil accounting for roughly a quarter of Italy's total crude imports. But the volume of its refined product exports exceeded that of its Libyan crude imports. Should the disruption force Italian and other refiners to decrease their runs, a sustained disruption in Libyan exports could result in decreased Italian product exports to other markets, tightening product markets well beyond the Mediterranean basin. At this time, however, Italian refinery runs have not been visibly affected by the current disruption.

Market conditions
The impact of a supply disruption is greatly affected by underlying market conditions, such as supply and demand balances, commercial and strategic stock inventory levels, and spare production, transportation and refining capacity. In 1973, the Arab oil embargo had an acute market impact because demand had been growing steeply and the market was already tight even before the event. But in 1967, an earlier Arab oil embargo ended in failure because the market was much more slack. The current disruption is occurring against a context of relatively comfortable spare capacity. Oil inventory levels are generally high by historical standards. But they are not evenly distributed throughout the world and are markedly tighter in Europe, the primary market for Libyan crude, than in North America. The European Brent market had been tightening before the start of unrest. In contrast, spare capacity in both transportation and refining remains abundant, which makes it possible to carry substitute barrels at a relatively low cost over long haul routes and to process barrels of a lesser quality than Libyan crude.

Because demand and supply are both subject to seasonal cycles, the time of year of a supply disruption affects its impact. The current disruption is occurring in a relatively low-demand season. Should it be prolonged, it could conflict with a seasonal ramp up in refinery production ahead of the peak summer driving season. Crude maintenance in the North Sea and elsewhere is also relatively low in the first quarter.

Strategic reserves
Countries with strategic reserves of crude oil and/or petroleum products must decide whether or not to release them in response to a disruption. The decision is a complex one whose potential benefits must be weighed against costs that include a reduction in pressure on suppliers with spare capacity to increase output, and a lower amount of reserves available for use in the future. Most of Europe's strategic oil reserves are held in products at refinery sites. The United States also holds its strategic reserves in both sweet and sour crudes which can meet a variety of market needs.

Transit corridors
A supply disruption does not necessarily come in the form of a loss at the wellhead, but can result from a transit blockage. Although Egypt is not a large exporting country, it is important to the oil markets as a transit corridor. Earlier this year, as unrest mounted in Egypt, the market grew concerned that oil traffic though the Suez Canal and the SUMED pipeline might be halted. A significant amount of internationally traded oil moves through a number of chokepoints, such as the Strait of Hormuz, the Strait of Aden, the Strait of Gibraltar, the Bosporus and the Malacca Strait, to name a few of the most well known, where it is vulnerable to bottleneck and transit risks. Unrest in Yemen might raise market worries about disruption in the Strait of Aden; although repeated attacks by Somali pirates have already taken a toll on local traffic, oil has continued to flow. In the past, Iran has occasionally raised the threat of retaliating by disrupting tanker traffic in the Persian Gulf if it came under attack. However, even during the Iran-Iraq war, oil continued to flow through Hormuz.

Domino effects
Unrest in one country can raise concerns about potential disruptions in another through a perceived risk of "contagion." Unrest and upheaval in economies that are non-critical to global oil supply might nevertheless rattle the markets by causing worries that they might spread to neighboring or politically- or culturally-related countries that may be of greater importance to energy market participants.

Market impact
Just as many factors may shape the market impact of a disruption, that impact may manifest itself through a variety of channels. Changes in prompt crude prices are just the most visible and immediate one. Other effects have to do with changes in the relative value of prompt oil supplies across the quality and grade spectrum, changes in the crack spread (the difference between crude prices and product prices) and in the time spreads, or shape of the futures curve. A loss of crude volumes with a high distillate yield will cause distillate prices, not just crude prices, to rise. A supply disruption can cause the price of prompt barrels to rise relative to that of barrels for later delivery - thus pushing the futures curve into backwardation, as opposed to contango (when futures prices are higher further into the future). Changes in the futures curve, in turn, carry implications for inventories and oil trade flows.