Before it launched the world’s biggest public listing, Saudi Arabian Oil Co. promised potential investors a small piece of a trillion-dollar company with access to unrivaled oil reserves. Not just in sheer volume but in climate friendliness, too. Aramco executives emphasized in the run-up to an IPO in 2019 that drilling Saudi oil generates fewer planet-warming emissions than other producers. “Not because our crude is cleaner than other crudes globally. It’s because of our standards,” Chief Executive Officer Amin Nasser said at a roadshow, pledging to do even more to deliver lower-carbon oil. “Even though our numbers are great, climate change is critical for the world.”

But Aramco’s accounting for greenhouse gas fails to provide a complete picture. The Saudi oil giant excludes emissions generated from many of its refineries and petrochemical plants in its overall carbon disclosures, according to a review of public filings by Bloomberg Green. Including all such facilities might nearly double Aramco’s self-reported carbon footprint, adding as much as 55 million metric tons of carbon dioxide equivalent to its annual tally—or about the emissions produced by Portugal.

Such missing data is a red flag for investors, who “need to be able to put a price on the climate risks that they are running in their portfolios,” said Nick Stansbury, head of commodity research at Legal and General Investment Management, which owns Aramco shares as of the end of 2020. “Those disclosures need to be comprehensive, true and accurate.”

In response to questions, Aramco said it will begin disclosing direct emissions from its full global operations this year. “We have a clear and deliberate path to increase the scope and details of [emissions] disclosure,” the company said in a statement. It added that current disclosure “reflects emissions from those assets where Aramco has the accountability and ability to manage and control emissions.”

Missing Emissions

Aramco’s disclosed direct emissions only account for “wholly owned, in-Kingdom” assets

Source: Aramco, Bloomberg

Note: Only Scope 1 and 2 emissions, in million metric tons of CO2 equivalent

Selective accounting helps burnish the low-carbon claims made on behalf of Saudi oil, which have become a key part of Aramco’s corporate identity. The company often cites a 2018 study published in the highly regarded journal Science that shows extracting oil in Saudi Arabia generates the second-lowest amount of emissions in the world, behind only Denmark.

But crude isn’t much use until it’s refined, and distilling black gunk into gasoline, jet fuel or diesel is emissions-intensive work. Much of this activity has been left out of company disclosures because Aramco chooses to report only emissions from facilities it wholly owns that are also located inside the kingdom. What’s more, Aramco is set to double its refining network’s capacity to handle as much as 10 million barrels a day by 2030; much of those emissions wouldn’t have been disclosed under the company’s past reporting practices.

Aramco’s accounting maneuver is made possible because many of its refineries are joint ventures or overseas, including the U.S., South Korea, Japan, China and Malaysia. To calculate those missing emissions, Bloomberg Green relied on estimates from refineries in more than 80 countries compiled in a study published in 2020 in the journal Nature Climate Change. The researchers accounted for variations in more than 300 different types of crude refined worldwide, with lower and upper estimates of emissions.

Adjusting these calculations for Aramco’s foreign facilities and its share of joint ventures shows a range for 2019 emissions between 75 million tons and 113 million tons. That gap reflects the difficulty in accurately estimating the carbon output of any particular refinery. Aramco declined to provide more precise figures. “We do not comment on emissions on an asset-by-asset basis,” the company said in its statement.