In 2015 the National Oceanic and Atmospheric Administration (NOAA) used satellite data from the Visible Infrared Imaging Radiometer Suite (VIIRS) to build the most accurate picture of global gas flaring ever conducted.
7467 individual flare sites were identified, with a total flared gas volume estimate of 143 billion cubic meters (BCM). This corresponds to 3.5% of global gas production.
The study found that 90% of the total gas flared occurred in upstream production areas, with a further 8% at refineries and 2% at liquefied natural gas (LNG) terminals. Of the flare sites identified in the study, 6802 were upstream flares, 628 were downstream sites and 37 flares were found at LNG terminals.
Accuracy is difficult
Despite being the best estimate of global flaring volumes ever produced, the results still do not reflect the exact volume of gas released into the atmosphere. The study was released in 2015, but the results of the study reflect the global flaring picture in 2012. The satellite imagery also did not capture cold flaring volumes.
Methane, the primary component of natural gas, is 40 times more potent as a greenhouse gas (GHG) than carbon dioxide (CO2). Flaring the gas converts the methane and associated noxious gasses into safer substances like CO2, but occasionally methane is released into the atmosphere through vents. Rather than being flared to convert the gas to CO2, methane is cold vented in its original state. Whilst methane’s potency declines over time, it contributes more to global warming than any other gas.
Energy companies can voluntarily report how much gas they flare, but a lack of independent data has resulted in uncertainty about how much gas is actually being lost in the process. Gas can also be lost to inefficient processes and leaks. While ultrasonic flare gas meters can be used to detect leaks through mass balance calculations, this is still not widespread enough throughout the world.
Which countries flare the most gas?
Satellite studies do identify geographical ‘hot spots’ for flaring. Chris Elvidge, lead scientist on the project at NOAA’s Earth Observation Group in Boulder, Colorado, said: “The most surprising thing I found was the large number of flaring sites there are in the USA. The flares in the USA are small and highly intermittent, but gosh, there are a lot of them, far exceeding any other country!”
The predominance of gas flaring in a specific region can be looked at in two ways. Regions that have the highest number of individual flare sites, and regions that release the most gas through flaring operations. From this perspective, the USA and Russia are the two main gas flaring nations. The USA has by far the highest number of flare sites at 2399, while Russia leads in terms of the volume of gas flared.
Russia flares around 35 BCM, followed by Nigeria at around 15 BCM, and Iraq and Iran both flaring around ten BCM. Russia also has the second largest number of flare sites at 1053. Moving down the scale, individual countries’ flare site numbers reduce significantly: Canada has 332 flare sites, Nigeria 325, and China 309.
Increased focus on flaring
Although the USA has the most flare sites, the country does not flare a large volume of gas. Flaring is used for safety reasons and as the main method of disposal for Oil & Gas facilities that lack the required infrastructure to capture, store, and sell natural gas. Despite lower volumes, the US Environmental Protection Agency (EPA) is re-examining the accuracy of its air pollution estimates from flaring near refineries following a lawsuit by four environmental organisations. The suit claims air samples near oil refineries in Houston showed elevated levels of volatile organic compounds, up to 100 times higher than levels reported under outdated and inaccurate formulas.
NOAA’s satellite-based verification system will be an important tool in the tracking of individual nations’ Intended National Determined Contributions (INDCs), which have been submitted by 187 countries as part of the Paris Agreement. INDCs are GHG reduction targets, and will eventually be submitted by all 195 signatory nations to the Paris Agreement. Along with the World Bank’s initiative aimed at eliminating gas flaring by 2030, this framework represents potential CO2 savings in the hundreds of millions of tons every year.