Using satellite technology to identify ‘super emitter’ gas flares in Nigeria

Methane is over 80 times more powerful than carbon dioxide as a warming gas in a 20-year timeframe, so reducing methane emissions is critical to fighting climate change. The Global Methane Pledge was launched at COP26 in Glasgow and 155 countries have since signed up to agree to take voluntary actions to contribute to a collective effort to reduce global methane emissions by at least 30 percent from 2020 levels by 2030. We discuss why, in the case of the oil industry, new tools need to be put in the hands of regulators to take action where operators fail to curb gas flaring, an important source of methane emissions.

Methane and oil production

Methane emissions attributable to human activity come from multiple sources but one significant source that should be relatively ‘low-hanging fruit’ in terms of control is the methane emitted as a result of gas flaring at oil production sites. Gas flaring occurs when natural gas (methane) is produced as a by-product of oil extraction. Flaring (the disposal of unwanted gas by burning) may occur for safety reasons – to cope with sudden increases in gas pressure during oil extraction for instance and so avoid a potential explosion. Flaring also occurs routinely, however, for example where a producer deems it uneconomic to capture and process the gas for use or sale.

According to the Global Gas Flaring Reduction Partnership, around 139 billion cubic meters of gas were flared in 2022 which, assuming a flare combustion efficiency of 98%, resulted in 350 million tonnes of CO₂ equivalent emissions. However, because methane has an 80 times more powerful greenhouse effect than CO₂, the methane emissions resulting from the 2% of natural gas that was released un-combusted due to flare inefficiency added a further 100 million tonnes of CO₂ equivalent emissions to this figure. The idea that flares routinely achieve 98% combustion efficiency may be an over-optimistic assumption and, in practice, actual global emissions from flaring could be significantly higher than the above estimates.

In addition to its climate impacts, flaring can have detrimental health impacts on populations close to flare sites. Black carbon, naphthalene and benzene can all be released into the air and may lead to increased levels of respiratory and heart disease, eye and liver damage, headaches, tremors and irregular heartbeats. The flaring of gas is also incredibly wasteful. The current annual global amount of gas flared would be sufficient to power the whole of sub-Saharan Africa.

Finding super emitters in Nigeria

Identifying the location and scale of existing methane emissions is clearly an important first step on the road to control and reduction. In the oil industry, while there are a number of different potential sources of methane emissions, flaring is a major one. Under the UK Foreign, Commonwealth and Development Office - funded FOSTER programme in Nigeria, we worked with the specialist company EnergyCC to demonstrate how satellite technology can be used to identify and measure gas flares. Our study delivered some startling findings, identifying onshore and offshore oil production facilities in Nigeria that were supposedly designed to avoid all routine flaring but which, in practice, flared at rates that put them in the ‘super emitter’ category, – or amongst the largest 300 (3%) of the 10,390 flares currently estimated to operate globally.

The pressure is on

In November 2023, the EU, a major importer of oil and gas, announced a new law to curb methane emissions both within Europe and within its supply chains. The law will oblige oil, gas and coal suppliers to properly measure, monitor, report and verify their methane emissions and take action to reduce them. Initially applying to EU producers, from January 2027, the regulation also requires that new import contracts for oil, gas and coal can be only concluded if the same monitoring, reporting and verification obligations are applied by exporters as for EU producers. The regulation will set out a methane intensity methodology and maximum levels to be met for new contracts for oil, gas and coal. This should be a spur for action for oil companies and regulators in oil-producing countries around the world for whom the EU is a major export market.

A new tool for regulators

Our work with EnergyCC demonstrates the urgent need for regulators to independently monitor gas flaring from oil production facilities and to take action to ensure companies adhere to operational best practice. It also demonstrates the utility of satellite-based approaches to monitoring gas flaring and the potential those techniques have to put critical data, often from remote and difficult to otherwise access facilities, into regulators’ hands.

With new regulations such as the EU’s methane emissions law coming in to force there is an even greater incentive for oil exporting countries and oil companies to use such tools to ensure effective action is taken quickly.

A short summary report on this work in Nigeria can be found here. In addition, two detailed technical reports are available, one looking at onshore facilities and the other offshore facilities.