Vahid Salemi/AP/File
In this 2008 file photo, Iranian oil technician Majid Afshari checks the oil separator facilities in Azadegan oil field, near Ahvaz, Iran. In the 1980s, when production quotas began to be based in part on oil reserves, Iran and many OPEC members reported huge increases in their reserves.

Does OPEC really have 80 percent of the world's oil? Maybe not.

OPEC's oil reserves haven't been independently verified, but there's evidence they've inflated the numbers. Here's why it matters.

Has OPEC misled us about the size of its oil reserves? The short answer is probably. The long answer is that currently, there is no way to know for sure.

The next question we should ask is: Does it matter? The answer is most definitely yes. OPEC, short for the Organization of Petroleum Exporting Countries, currently claims that its 12 members hold 81.3 percent of the world's oil reserves. And, with few exceptions the world believes them. Trouble is these reserves "are not verified by independent auditors," according to a study (PDF) done by the U.S. Government Accountability Office, the nonpartisan investigative arm of the U.S. Congress. OPEC reserves are simply self-reported by each country. Essentially, OPEC's members are asking us to take their word for it. But should we?

It ought to give us pause that the reserve numbers OPEC countries release are used in major reports produced by the U.S. Energy Information Administration (EIA); the Paris-based International Energy Agency (IEA), a consortium of 28 of the world's oil importing nations; oil giant BP which annually publishes the widely cited BP Statistical Review of World Energy; and myriad other organizations. Reports from the two agencies cited above and BP are frequently consulted by governments, industry, banks and investors around the world for policy formulation, long-term planning, and lending and investment decisions. Yet these groups seem blissfully unaware of the caveats surrounding the numbers in those reports and by extension surrounding more than 80 percent of the world's oil reserves.

Keep in mind as we go along that the sometimes astronomical numbers thrown around for world oil reserves by the uninformed or by those who intend to mislead us either have no basis in fact or actually refer to "resources." Resources are only an estimate of oil thought to be in the ground based on rather sketchy evidence. And, most of that oil will never be recoverable. Reserves, however, are what can be produced at today's prices from known fields using existing technology. It turns out that reserves are only a tiny fraction of so-called resources.

Now here's the caveat from the International Energy Agency in its World Energy Outlook 2010:

Definitions of reserves and resources, and the methodologies for estimating them, vary considerably around the world, leading to confusion and inconsistencies. In addition, there is often a lack of transparency in the way reserves are reported: many national oil companies in both OPEC and non-OPEC countries do not use external auditors of reserves and do not publish detailed results.

"National oil companies" refers to government-owned companies which typically control all oil development within a country.
The BP Statistical Review of World Energy for 2012 provides this explanatory note under a table listing oil reserves by country:

The estimates in this table have been compiled using a combination of primary official sources, third-party data from the OPEC Secretariat,World Oil, Oil & Gas Journal and an independent estimate of Russian and Chinese reserves based on information in the public domain. Canadian oil sands 'under active development' are an official estimate. Venezuelan Orinoco Belt reserves are based on the OPEC Secretariat and government announcements.

The key words are "OPEC Secretariat" which refers to the OPEC staff located in an office in Vienna. That office is where BP presumably gets its information about OPEC reserves. The EIA lists the OPEC Annual Statistical Bulletin put out by--you guessed it--the OPEC Secretariat. Alas, theAnnual Statistical Bulletin tells us under the heading "Questions on data" that "[a]lthough comments are welcome, OPEC regrets that it is unable to answer all enquiries concerning the data in the ASB." In other words, trust us. So, information about OPEC reserves comes either from the OPEC offices in Vienna or from member countries. Some analysts may adjust those figures based on the few shreds of evidence that are available outside of official government pronouncements. But, in reality, there are almost no hard facts when it comes to OPEC reserves.

Strangely, many of these countries say that a detailed audit of their fields by independent observers is out of the question because oil reserves are a state secret. And, yet those countries report their reserves to OPEC which publishes them for all to see. So, are oil reserves in many OPEC countries a state secret or not? Apparently, what's secret is the field-by-field data that would tell us whether the reserves claimed by these countries are actually there. Are there reasons to believe that if we saw this data it would contradict the official overall number provided by some countries? In a word, yes.

First, OPEC allocates production levels among its members. It does this to control the flow of oil to world markets and thus to manipulate the price. OPEC bases production quotas for its members in part on the size of each member's reserves. When this policy was first established in the 1980s, reported reserves for several OPEC members jumped between roughly 40 and 200 percent within one year--not always the same year--as each country jockeyed for a higher production quota. Based on EIA data, here's what it looked like:

Country Reserves in Barrels (Year) Reserves in Barrels (Year) Percentage Increase
Iran 48.8 billion (1987) 92.9 billion (1988) 90.4%
Iraq 47.1 billion (1987) 100 billion (1988) 112.3%
Kuwait 66.7 billion (1984) 92.7 billion (1985) 39.0%
Saudi Arabia 172.6 billion (1989) 257.6 billion (1990) 49.3%
United Arab Emirates 33.1 billion (1987) 98.1 billion (1988) 196.4%
Venezuela 25.0 billion (1987) 56.3 billion (1988) 125.2%

Not every country participated in the free-for-all. But the countries with the largest exports participated with a vengeance. There was no drilling program in any of these countries that could have explained such jumps in reserves.

The competition continues to this day. In October 2010 Iraq announced an increase in its oil reserves from 115 billion barrels to 143.1 billion barrels. No attempt was made to hide the reason for the increase: "Falah al-Amri, the head of the country’s State Oil Marketing Company, suggested that future quota calculations might have been a factor in the revision." A week later Iran raised its reserves number from 136.6 billion barrels to 150.3 billion barrels, presumably in order to maintain its position within the OPEC production quota system. These numbers have been dutifully included in the latest statistical compilations of both EIA and BP, as if the two hadn't gotten the memo that Iraq's and Iran's increases were reported merely for quota reasons and not because of any particular discoveries.

Perhaps even more astounding is that some OPEC members don't even take the oil reserves reporting game seriously any more. Logic dictates that there should be at least small adjustments up or down in reserves each year as new fields are developed and old ones decline. The world of geology simply cannot yield precisely the new reserves needed to replace exactly the amount of oil extracted from existing fields each year. 

And yet, the United Arab Emirates has been reporting 97.8 billion barrels of oil reserves every year since 1997. Kuwait has been reporting 104 billion barrels each year since 2008. Iraq shows long periods from 1980 onward when reserves don't change, the latest running from 2004 to 2011 during which reserves supposedly held absolutely steady at 115 billion barrels. Algeria has reported 12.2 billion barrels from 2008 onward. At leastSaudi Arabia has demonstrated a certain sensitivity to appearances and has adjusted its reserves number slightly from year to year. And yet, that number has remained within a narrow range of 260 to 267 billion barrels from 1991 to the present. All of these numbers suggest that depletion from existing fields is taking absolutely no toll on OPEC's reserves. Even if that's true, we have no way of verifying it.

The second reason to doubt OPEC's official oil reserve numbers is that two insiders have told us not to trust those numbers. The now deceased A. M. Samsam Bakhtiari, an executive for the National Iranian Oil Company, told the Oil & Gas Journal all the way back in 2003 the following: "I know from experience how 'reserves' are estimated in major Middle Eastern (and OPEC) countries...And the methods used are usually far from scientific, as the basic knowledge for such a complex exercise is not at hand." He estimated that Iranian reserves were about 37 billion barrels, not the 90 billion that were being cited at the time.

Back in 2007 Sadad al-Husseini, former executive vice president for exploration and production at Saudi Aramco, the state oil company that controls all oil development in Saudi Arabia, told a conference in London that world oil reserves had been inflated by 300 billion barrels. That number almost matches the increases in OPEC members' reserves for quota reasons in the 1980s, and it represented about a quarter of all reported reserves in 2007. As a result, to this day al-Husseini remains skeptical of claims that world oil production will rise much from here.

Another piece of evidence that casts doubt on OPEC members' reserve claims came to light in 2005. That year Petroleum Intelligence Weekly, an industry newsletter with worldwide reach, obtained internal documents from the state-owned Kuwait Oil Co. The documents revealed that Kuwaiti reserves were only half the official number, 48 billion barrels versus 99 billion. Since then policymakers and the public seemed to have ignored the entire incident. The BP Statistical Review lists Kuwait's reserves as 101.5 billion barrels as of 2011. The EIA shows them as 104 billion. Skepticism apparently is taking an extended holiday at BP and EIA.

Measuring oil reserves remains something of an art. Even large publicly traded oil companies with armies of petroleum geologists and engineers who operate under strict U.S. Securities and Exchange Commission rules for estimating reserves--even these companies don't always get it right. In 2004 Royal Dutch Shell had to lower its reserves number by 20 percent, a huge and costly blunder for such a sophisticated company. If Shell can bungle its reserves estimate, then how much more likely are OPEC countries which are subject to virtually no public scrutiny to bungle or perhaps manipulate theirs.

I said in a previous piece that the rate of production is the key metric when evaluating the success of the world's oil production and delivery system. But sustained production of oil depends on the size and quality of reserves. If the world does indeed have 300 billion fewer barrels of reserves than it thinks it does, that has implications for how long the current rate of production can be maintained. (It has been stuck between 71 and 76 million barrels per day since 2005.) And, that is why the mystery surrounding OPEC's reserves, which supposedly constitute 80 percent of the world's reserves, is so disturbing. Even more disturbing is how much this mystery is ignored or perhaps not understood by policymakers, industry and the public.

We shouldn't be the least bit exultant over claims that we have more oil reserves than we've ever had before. First, we are using up that oil at a faster rate than ever before. Second, much of what is currently parading as reserves may not be. Third, the plateau in worldwide oil production since 2005 is actually consistent with a smaller reserve base.

Given all this I think we can safely say that when it comes to the official statistics on oil reserves, there is likely to be less than meets the eye. And that begs the question: Does it really make sense for the world to chart its energy future based on such dubious information?

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