A guide to monitoring and quantifying methane emissions from the oil and gas sector
More than a year after 110 countries signed onto the Global Methane Pledge at COP26 in Glasgow, nations are starting to make progress in enacting regulations to reduce methane emissions.
Time for action
Methane has more than 80 times the warming power of carbon dioxide over a 20-year period and is responsible for 0.5°C of the warming the earth has experienced since pre-industrial times. Because of its potency and short lifespan compared to carbon dioxide — methane only stays in the atmosphere for 12 years — cutting methane pollution is the fastest way to slow the accelerating rate of global warming. We cannot limit global warming to 1.5 degrees or 2 degrees without drastically reducing anthropogenic methane emissions.
Yet, according to the U.S. National Oceanic and Atmospheric Administration, the concentration of methane in the atmosphere is increasing, and at ever faster rates, with the highest-ever recorded rise in 2021. Anthropogenic emissions are one of the most important drivers of this increase. In this decade, we must make significant progress cutting emissions across all three major methane emitting sectors – energy, agriculture, and waste – but some of the biggest opportunities are in the energy sector, specifically oil and gas.
The oil and gas industry is one of the main methane polluters, responsible for 21% of all anthropogenic emissions. Methane, being the main component of fossil gas, is released from all parts of the oil and gas production chain, from extraction and processing to the transport phases. Some of the releases are intentional. This is the case in some oil extraction operations, where the gas extracted alongside the oil is considered waste and is either released into the atmosphere (vented) or burned (flared). Gas is also intentionally released during maintenance procedures or from equipment that emits gas by design, like automated pneumatic valve controllers that are driven by pressurised fossil gas. The other type of releases are ubiquitous unintentional emissions. Methane escapes from leaky valves, open hatches, poorly maintained storage tanks, etc. In total, eliminating vents, flares, and leaks is a huge opportunity for methane emission mitigation. In many cases the gas that is saved can be sold, making efforts to reduce emissions profitable.
Until a few years ago, detecting leaks and quantifying emissions was a slow and expensive task. Fortunately, this has changed. We experienced this change firsthand. For the last two years, we have been documenting methane emissions at oil and gas facilities around the world using a FLIR GF320, one of many optical gas imaging cameras available on the market, to find and identify methane leaks. Since February 2021, we have visited more than 500 sites across 15 countries, mostly in Europe. We found emissions coming from flaring, malfunctioning equipment, and leaks at nearly 70% of the sites we visited. Based on these results, we launched a campaign in Europe, #CutMethaneEU, to raise awareness of the problem of methane pollution in the oil and gas industry. We are now convinced that the growing set of tools can underpin smart policy that will help us efficiently eliminate methane pollution.
Monitoring and quantifying emissions
Owing to recent technological advances, the oil and gas industry, scientists, and authorities can now tap into a growing set of tools that can help them detect and quantify methane emissions. Ranging from specialised handheld cameras that help technicians pinpoint leaks to space-borne instruments that can quantify regional emissions, these tools are changing our understanding of methane emissions and expanding the available approaches toward target setting, monitoring, and compliance.
The first task these technologies facilitate is the cost-effective screening of oil and gas facilities for methane leaks and pinpointing the exact location of the leak to allow its repair. Frequent monitoring of methane leaks is an integral part of safety operations and environmental standards, so regulators and operators are looking into ways to make Leak Detection and Repair (LDAR) programmes utilising these technologies as efficient and cost-effective as possible. The frequency and efficiency of such work is crucial since even a small leak left undetected for a long period of time could release a significant amount of methane into the atmosphere.
The second crucial task achieved by new technologies is quantifying methane emissions at different scales, from the equipment to the national level, which can serve many purposes. For example, quantifying emissions within a facility can help decisionmakers understand the relative importance of emissions sources and prioritise mitigation accordingly. Reliable information about the total emission intensity of a company (i.e., the amount of methane emissions released during the production of a barrel of oil or a cubic metre of gas) can help buyers procure oil and gas that meets their environmental standards and that will help them reduce their indirect emissions. At a regional and national level, quantifying and keeping track of methane emissions is necessary for regulatory compliance, for setting and tracking methane reduction goals, and for reporting methane emissions to international bodies.
Up to now, emission from the company to the national level are calculated using a “bottom-up” approach, i.e. based on the quantity of various types of equipment used by each site or company (number of tanks, kilometres of pipelines, etc.) and information about the typical emissions for each of these types of equipment (also called the “emission factor” of the equipment). Unfortunately, these emission factors are frequently outdated, don’t reflect the conditions in which each piece of equipment operates, and very typically don’t take into account abnormal operating conditions such as malfunctions or maintenance.
Fortunately, the increasing number of new monitoring solutions available is supporting both the detection and quantification of methane emissions throughout the oil and gas value chain. Based on the rise of key enabling technologies — like miniaturised electronics, advanced algorithms, and low-cost access to space — and fueled by increased international awareness of the methane impacts, these novel solutions have the potential to greatly improve our ability to identify and address methane pollution sources. The variety of solutions is vast and includes instruments operated from the ground, air, and space.
Ground-based instruments
Ground-based instruments include mobile or fixed instruments that utilise spectroscopic, optical, acoustic, and mass balance techniques. They include hand-held infrared gas imaging cameras, like those used by CATF as described above, that visualise emissions as they occur from an individual leak or venting source, and fixed sensors that are continuously monitoring an area for the increased presence of methane in the air. Some ground-based devices can quantify leaks, while others are used primarily for detection.
Airborne instruments
Airborne instruments consist of mobile measuring devices attached to airplanes and, increasingly, drones. Measurements from such instruments include advanced spectroscopic cameras for detecting methane plumes below an aircraft and instruments used to quantify methane concentrations in the air an aircraft flies through. These data are combined with wind information and advanced algorithms to both detect emissions and quantify their magnitude. Airborne measurement campaigns are resource-intensive but have been quite effective in mapping point source emissions and total methane flux from entire production regions, like the Permian Basin in the United States.
Spaceborne instruments
Spaceborne instruments include a range of advanced multispectral and hyperspectral cameras mounted on satellites. Some instruments are designed to characterise methane concentrations in the atmosphere over large swaths of areas, such as production basins and tropical wetlands, while other instruments are designed to detect large emissions sources (known as “super-emitters” and “ultra-emitters” depending on their size), from facilities around the world.
Airborne and spaceborne cameras are the technologies that have generated the most excitement in recent years. Such instruments can be used to map methane emissions over large areas and have already changed our understanding of emissions, highlighting that previously unexpected very large emitters are in fact ubiquitous. Combined with advanced modeling techniques, these measurements allow the estimation of total emissions from large oil and gas production areas, repeatedly demonstrating that current bottom-up emission estimates are underestimated. A new generation of high-resolution satellite instruments, such as the Canadian GHGSat, promises to both detect and quantify emissions at the individual facility level, directly helping both total methane accounting and guiding mitigation programmes. Importantly, such instruments do not require access to the facility, so they can be used by regulators, investors, and other stakeholders to independently check emissions reported by companies.
Despite these rapid advancements, there are some limitations to current and planned satellite technology. Minimum detection limits are currently high (approximately 500 kg per hour for freely available datasets and 100 kg per hour for commercial datasets), which means that they are unable to “see” many smaller but potentially widespread emissions sources that fall below this threshold. While these detection limits are expected to come down to 50-100kg per hour for some freely available datasets (e.g., Carbon Mapper) in 2023, they will still be much larger than the detection limits of airborne and ground-based instruments. Moreover, spaceborne instruments cannot yet detect methane at night, cannot see through clouds and face difficulties in highly heterogeneous terrain (e.g., mountainous regions). Some of these limitations can be overcome by new instrument designs and better algorithms. For example, researchers have only recently proven that satellites can be used to monitor emissions from offshore platforms, a feat that was considered impractical before. By 2025, some estimates suggest that satellites will be able to image approximately 50% of point source emissions around the world.
Looking beyond purely technological developments, the next great challenge is to transform the current set of promising technologies into a useful monitoring system that will drive action to mitigate methane emissions. This should be done in at least three directions. First, there is a need to develop globally recognised testing standards and facilities that will be used to evaluate the effectiveness of each proposed measurement technique. The development of such standards will create trust in the provided data, lower the barriers for new players to enter the market, and allow rapid diffusion of new technologies across the globe. Second, different technologies should be integrated into a multi-tier observing system that will combine their strengths to adaptively monitor emissions at different scales. Efforts to build such a system are spearheaded by the International Methane Emission Observatory, part of the United Nations Environment Program, which will combine observations from different satellite platforms to achieve global monitoring of high-emitting events. Third, the industry needs to adopt detailed measuring and reporting protocols that will help it perform measurements in a robust and trustworthy way. Such protocols are already being developed, e.g., in the Oil and Gas Methane Partnership (OGMP) 2.0 framework, led by the United Nations Environment Program and the Climate and Clean Air Coalition, and the Veritas initiative led by the U.S.-based GTI Energy. However, convergence and wider adoption of these protocols is needed to allow quick mitigation results. Developments in these directions are forming the groundwork on which smart, data-driven policy can be developed and implemented.
Framing the methane mitigation case
The case for strong oil and gas methane regulations around the world is clear. Regulating methane emissions from this sector is one of the fastest, most cost-effective, and most impactful actions governments can take to achieve their climate goals. The International Energy Agency (IEA) estimates the oil and gas industry can eliminate nearly 75% of the methane emissions globally by using available technologies today, at little to no cost. This is based on the average price of gas from 2017 to 2021, which was much lower than the average price of gas for 2022. Higher gas prices, such as those seen over the last year, mean that even more emissions can be cut at zero cost or even profitably.
Governments also don’t have to start from scratch: a number of successful regulations and best practices can guide their work. At Clean Air Task Force, we have compiled and published a Compendium of Leading North American Regulations and Emission Standards, which contains “best in class” regulations for each major specific emissions sources including control requirements, monitoring, record keeping, and reporting rules for each. We have also designed the Country Methane Abatement Tool (CoMAT), software that guides environmental and climate ministries in designing appropriate regulatory strategies for reducing methane from the oil and gas ministry in a given country.
Many other resources are available. For example, the IEA has vast list of technical resources aimed at understanding and quantifying methane emissions at national and regional scales, as well as a guide for governments and policymakers on how to design and implement methane-specific regulations. Another key resource is the Methane Guiding Principles Partnership’s Best Practice Guide, which contains a detailed list of available technologies and protocols for mitigating methane emissions throughout the oil and gas value chain. These guidelines consider even the initial stages of a project, from engineering, design, and construction.
While all previous guidelines cover most of the oil and gas value chain and some parts of the life cycle of production wells, none include mitigation guidelines for abandoned wells. Until recent years, emissions from abandoned wells had been poorly analysed and understood. We know now that emissions from abandoned wells can vary by several orders of magnitude and the sooner we start requiring practices to prevent wells from being abandoned without being properly plugged, the better we will address this emissions source.
Advancing policy around the world
Momentum for stronger and smarter regulation is starting to build around the world, as countries are setting ambitious targets for reducing oil and gas methane. In 2022, Nigeria became the first sub-Saharan country to regulate methane emissions from its oil and gas sector while Colombia became the first to do so in South America. In the same year, Mexico committed to develop an investment and implementation plan to eliminate routine venting and flaring. In North America, the United States recently announced a goal of achieving 87% reductions in methane emissions from covered sources by 2030 from 2005 levels through recently proposed regulations, which also include the creation of a novel “super emitter response programme.” Canada is developing a regulatory framework that will cut oil and gas methane emissions 75% below 2012 levels by 2030. The European Union is in an advanced stage of preparing a methane regulation, incorporating aspects of the OGMP 2.0 measurement framework, that aims to reduce, quantifying, and reporting methane emissions from this industry.
At the same time as these regulatory approaches are being developed and implemented, the new technological developments underpin recent efforts to coordinate energy importers and exporters to lower methane emissions across the value chain. For example, the United States, European Union, Japan, Canada, Norway, Singapore, and the United Kingdom issued a Joint Declaration from Energy Importers and Exporters on Reducing Greenhouse Gas Emissions from Fossil Fuels, committing to reducing greenhouse gas emissions across the fossil fuel energy value chain based on robust and transparent measurement and reporting of global methane emissions. The European Union, being the largest gas importer in the globe, contemplates in the methane regulation currently under discussion the use of top-down technologies to monitor methane emissions outside its borders. The European Union will have to explore paths to set methane emission standards on imported gas if it wants to show international leadership on this front.
In short, the oil and gas sector is one of the main drivers of the increase in global atmospheric methane concentrations. Methane leaks from this industry are unpredictable and occur throughout the oil and gas value chain. In order to improve methane emission estimates and facilitate emission reductions, we need to move from traditional methodologies of estimating methane leaks that treat emissions rates as constant factors, to new top-down approaches that quantify real-time emissions at local, regional, and global scales. Thus, it is critical that mitigation policies around the world utilise the many recent advances in methane leak detection technologies to shape and target mitigation efforts.
This article was originally published in the February 2023 edition of AWE Magazine.
