- What is gas flaring?
- Why is gas flared?
- What are the environmental impacts of gas flaring?
- How can we reduce the amount of gas being flared?
- What is being done about gas flaring?
What is gas flaring?
Gas flaring is the burning of the natural gas associated with oil extraction. The practice has persisted since the beginning of oil production over 160 years ago. It takes place due to a range of issues, from market and economic constraints, to a lack of appropriate regulation and political will. Flaring is a waste of a valuable natural resource that should either be used for productive purposes, such as generating power, or conserved. For instance, the amount of gas currently flared each year – about 140 billion cubic meters – could power the whole of sub-Saharan Africa.
Why is gas flared?
Flaring persists to this day because it is a relatively safe, though wasteful and polluting, method of disposing of the associated gas that comes from oil production. Utilizing associated gas often requires economically viable markets for companies to make the investments necessary to capture, transport, process, and sell the gas.
Flaring may be required for safety reasons. Extracting and processing oil and gas involves dealing with exceptionally high, and changeable, pressures. During crude oil extraction, a sudden or dramatic increase in pressure could cause an explosion. Although rare, industrial accidents involving oil and gas can result in destructive, dangerous, and long-lasting fires that are difficult to contain and control. Gas flaring allows operators to de-pressurize their equipment and manage unpredictable and large pressure variations by burning any excess gas.
Economic and technical reasons
In many cases, oil fields are located in remote and inaccessible places. These sites are hard to access and may not produce consistent or large volumes of associated gas that operators can use. This can make it logistically and economically challenging to transport associated gas to where it can be processed and utilized. Additionally, capturing and using the associated gas is often viewed as prohibitively expensive if oil production sites are small and dispersed over a large geographic area. In these instances, the associated gas is typically flared.
Sometimes, where it's impossible to utilize the gas, the local geology will allow it to be conserved by re-injection back into the reservoir. However, this too, is not always feasible despite recent technological advances.
In some cases, while capturing and utilizing associated gas is economically and technically feasible, a country's laws and regulations might make it difficult for, or even forbid, companies from commercializing associated gas. For example, a company may have secured the rights to extract oil but may not have the right to use the associated gas produced during extraction. In other instances, regulations may not specify how associated gas is to be handled commercially. This creates legal ambiguity on how associated gas should be processed. Additionally, regulations that impose penalties on companies that flare gas may not always be effective at curtailing the practice, and especially if flaring and paying a penalty is more economically viable than capturing the gas and selling it. GGFR works with governments to help create the right policies and regulations so that routine flaring comes to an end and the associated gas is used for productive purposes.
What are the environmental impacts of gas flaring?
Thousands of gas flares at oil production sites worldwide burned approximately 139 billion cubic meters of gas in 2022. Assuming a ‘typical’ associated gas composition, a flare combustion efficiency of 98% and a Global Warming Potential for methane of 28, each cubic meter of associated gas flared results in about 2.6 kilograms of CO2 equivalent emissions (CO2e), resulting in over 350 million tonnes of CO2e emissions annually, of which around 42 million tonnes is emitted in the form of unburnt methane.
The methane emissions resulting from the inefficiency of the flare combustion contribute significantly to global warming. This is particularly so in the short to medium term as, according to the Intergovernmental Panel on Climate Change, methane is over 80 times more powerful than carbon dioxide as a warming gas on a 20-year timeframe. On this basis, the annual CO2e emissions from flaring increase to around 126 million tonnes.
Flaring is, of course, totally unproductive and can be avoided far more easily than many other sources of greenhouse gas (GHG) emissions. The gas could be put to good use and potentially displace other more polluting fuels, such as coal and diesel, that generate higher emissions per energy unit.
In addition to these GHG emissions, black carbon - more commonly known as soot - is another pollutant sometimes released by gas flares. Black carbon is produced through the incomplete combustion of fossil fuels and, despite remaining in the atmosphere for just a few days or weeks, has a very large climate impact. This is of particular concern in the Arctic, where black carbon deposits are believed to increase the rate at which snow and ice is melting. Research from the European Geosciences Union indicates that gas flaring emissions may contribute about 40 percent of the annual black carbon deposits in the Arctic.
How can we reduce the amount of gas being flared?
Oil producers can either re-inject associated gas or use it for productive purposes. However, operators often face significant challenges capturing, treating, storing, transporting, and commercializing associated gas, and the cost of ending all routine flaring could be more than US$100 billion.
The traditional approach to flare gas utilization – collecting associated gas and transporting it through a gas pipeline – is heavily dependent on achieving economies of scale. To be viable, operators must typically capture a large quantity of associated gas from many flare sites, ideally located close to one another, and then build the infrastructure needed to commercialize the gas. For example, to generate power and increase energy access.
There are, however several alternative ways to address the routine gas flaring problem. Oil operators can re-inject associated gas back into the ground or build the infrastructure needed to capture, treat, store, and transport the associated gas to market. Meanwhile, governments can put in place a range of effective regulations and policies to incentivize and encourage gas flaring reduction.
Developments in small-scale gas utilization technologies have also greatly improved the potential for associated gas use in recent years. However, not all such technologies are economical, and much depends on fuel and end-product prices. Small electricity generation plants, truck-mounted, liquefied natural gas plants, and integrated compressed natural gas systems are often viable alternatives to flaring – but they can be expensive and even loss-making for an operator.
What is being done about gas flaring?
Encouragingly, while oil production has increased by roughly 26 percent since 1996, the amount of associated gas flared has decreased by 16 percent. This means that the oil industry is making progress because we are seeing a gradual decoupling of a long-standing correlation between oil production and gas flaring.
Many oil field operators who flare associated gas, are making the investments necessary to reduce flaring. Many have also made the commitment to end routine flaring.
In 2015, the World Bank and the UN Secretary-General launched the Zero Routine Flaring by 2030 (ZRF) initiative, which commits governments and oil companies to not routinely flare gas in any new oil field development and to end existing (legacy) routine flaring as soon as possible and no later than 2030.