Flare gas is excess or unwanted gas that gets burned off at industrial facilities, most visibly at oil refineries and drilling sites. You’ve likely seen the tall stacks topped with open flames along highways near petrochemical plants. That flame is flare gas being combusted, a controlled burn that serves as both a safety mechanism and a waste disposal method for gases that can’t be economically captured or safely stored. Globally, about 151 billion cubic meters of associated gas was flared at oil, gas, and liquefied natural gas facilities in 2024, according to World Bank satellite data.
Why Industrial Facilities Burn Off Gas
Flare gas exists because many industrial processes produce flammable gases that need to go somewhere. The most critical reason for flaring is safety. When equipment at a refinery or chemical plant gets over-pressured, relief valves automatically release gas to prevent explosions. That gas travels through piping to the top of a tall vertical flare stack, where it’s ignited. Without this system, a pressure buildup could rupture vessels and cause catastrophic failures.
Beyond emergencies, flaring happens during planned events too. When a plant starts up or shuts down, operators need to burn off gases that accumulate during the transition. At oil drilling sites, the situation is different: crude oil often comes up from the ground with “associated gas” dissolved in it, similar to carbonation in a soda. In remote locations where there’s no pipeline to carry that gas to market, operators flare it rather than let it escape raw into the air.
Flaring vs. Venting
The alternative to flaring is venting, which means releasing the gas directly into the atmosphere without burning it. Flaring is considered the lesser of two evils. Methane, the primary component of natural gas, is more than 28 times as potent as carbon dioxide at trapping heat in the atmosphere. Burning methane converts a portion of it into carbon dioxide, which still contributes to climate change but has a significantly lower warming effect than releasing raw methane. That conversion is why regulators generally require flaring over venting whenever possible.
How Efficient Flares Actually Are
A well-functioning flare doesn’t destroy 100% of the gas it burns. Under calm conditions, a standard utility flare achieves combustion efficiency above 96.5%. But weather changes the equation significantly. Research published in the Journal of the Air & Waste Management Association found that when crosswinds exceed 10 miles per hour, efficiency drops rapidly. At wind speeds above 30 mph, combustion efficiency can fall below 70%, meaning nearly a third of the gas passes through the flame unburned. That unburned gas, mostly methane, escapes into the atmosphere, a phenomenon called “methane slip.”
This matters because many flare stacks operate in exposed, windy environments like offshore platforms and open plains in oil-producing regions. The gap between theoretical efficiency and real-world performance means flaring releases more pollution than design specs suggest.
What Flaring Releases Into the Air
Even when a flare burns efficiently, the combustion produces carbon dioxide, nitrogen oxides, sulfur dioxide, carbon monoxide, black carbon (soot), and various volatile organic compounds. The specific mix depends on what’s in the gas being burned and how completely it combusts. Incomplete combustion makes things worse, releasing more soot particles and organic compounds.
For communities near flare sites, these aren’t abstract concerns. An estimated 500,000 Americans live within three miles of natural gas flares. A 2024 study in GeoHealth calculated that flaring and venting emissions in the United States cause roughly 710 premature deaths per year, along with 73,000 childhood asthma episodes, 92 childhood asthma emergency department visits, and about 130 respiratory hospitalizations annually. Researchers have also found links between flaring activity and increased risk of preterm birth in Texas’s Eagle Ford Shale region and higher rates of respiratory hospital visits in North Dakota. The total health damage from U.S. flaring and venting is estimated at over $7.4 billion per year.
Where the Most Flaring Happens
The nine largest gas-flaring countries in 2024 were Russia, Iran, Iraq, the United States, Venezuela, Algeria, Nigeria, Libya, and Mexico. Russia consistently leads the list, largely because of the vast distances between its oil fields and gas processing infrastructure. In many of these countries, flaring persists because building the pipelines and compression stations needed to capture associated gas costs more than the gas itself is worth, especially in remote areas or where oil prices make gas a low-priority byproduct.
Alternatives to Burning It Off
Flare gas doesn’t have to be wasted. Gas recovery systems can capture it before it reaches the flare tip and redirect it for useful purposes. The most straightforward option is reinjecting the gas back underground, which can also help maintain pressure in oil reservoirs and boost production. Where infrastructure exists, the gas can be processed and fed into pipelines for sale. In more remote settings, small-scale generators can convert flare gas into electricity to power the drilling operation itself or nearby facilities.
More experimental approaches are also in development. Researchers have explored integrating flare gas with solar power systems to generate both electricity and clean water, using the gas as fuel for advanced combustion cycles. These technologies aim to squeeze value from a resource that would otherwise just become pollution.
The Push to End Routine Flaring
The World Bank launched its “Zero Routine Flaring by 2030” initiative in 2015, drawing a distinction between safety flaring (which will always be necessary) and routine flaring (which happens simply because capturing the gas isn’t convenient or profitable). Endorsing governments commit to creating regulations that discourage routine flaring, while endorsing oil companies pledge to eliminate it from both new and existing production sites by 2030. The initiative’s endorsers now account for roughly 60% of total global gas flaring.
Despite that commitment, the 151 billion cubic meters flared in 2024 shows the gap between pledges and reality. Routine flaring continues in large part because enforcement varies widely between countries, and the economics of gas capture still don’t pencil out at many remote sites. The push to reduce flaring is as much an infrastructure problem as a regulatory one: until pipelines, processing plants, and local power grids reach the places where gas is being flared, the flames will keep burning.