Mitigating emissions in our operations

As we seek to increase production of oil and natural gas to meet growing global energy demand, we are committed to mitigating greenhouse gas emissions within our operations.


In this article

Mitigating emissions in our operations

Managing emissions

In the near term, we are working to increase energy efficiency and reduce flaring, venting and other emissions in our operations. In the medium term, we are deploying proven technologies such as cogeneration and carbon capture and storage where technically and economically feasible. Longer term, we are conducting and supporting research to develop breakthrough technologies. Since 2000, ExxonMobil has spent more than $10 billion to develop lower-emission energy solutions.

ExxonMobil has a robust set of processes to improve efficiency, mitigate emissions and contribute to effective long-term solutions.

These processes include, where appropriate, setting tailored objectives at the business, site and equipment levels, and then stewarding progress toward meeting those objectives. We believe this rigorous bottom-up approach is the most effective way to drive efficiency improvement and reduce greenhouse gas emissions, and that continuing to use this approach will yield further improvements in all sectors of our business.

For information on how ExxonMobil manages the business risks of climate change, please see ExxonMobil’s Energy and Carbon Summary.

Performance and initiatives 

We continue to manage our greenhouse gas emissions by strategically using proven processes and technologies. In 2017, ExxonMobil’s net equity greenhouse gas emissions were 122 million CO2-equivalent metric tons. Relative to our 2016 performance, our 2017 emissions decreased by approximately 1 million CO2-equivalent metric tons. This decrease was primarily driven by flaring reductions in Angola.

Chart — In 2017, ExxonMobil’s net equity greenhouse gas emissions were 122 million CO2-equivalent metric tons. Relative to our 2016 performance, our 2017 emissions decreased by approximately 1 million CO2-equivalent metric tons.

Chart — Our normalized greenhouse gas emissions from our Upstream, Downstream and Chemical operations was 24.2 metric tons per 100 metric tons of throughput or production in 2017. Over the past decade, increases in Upstream emissions have been largely offset by improvements in our Downstream and Chemical operations. We are committed to reducing our normalized greenhouse gas emissions through structured processes and the continued use of a bottom-up approach.
Chart — In 2017, greenhouse gas emissions avoided from ExxonMobil actions were 23.4 million metric tons. Since 2008, we have avoided 168 million metric tons of greenhouse gas emissions as a result of ExxonMobil actions.
*Our calculations are based on the guidance provided in American Petroleum Institute’s Compendium of Greenhouse Gas Emission Estimation Methodologies for the Oil and Gas Industry and IPIECA’s Petroleum Industry Guidelines for Reporting Greenhouse Gas Emissions. We report greenhouse gas emissions on a net equity basis for our business operations, demonstrating a share of emissions from any facility or operation in which ExxonMobil holds a financial interest, with the share reflecting the equity interest.

Energy efficiency

Energy used in our operations generated more than 75 percent of our direct greenhouse gas emissions in 2017 and continues to represent one of our largest operating costs. As such, we have focused on energy efficiency for many decades. Since 2000, we have used our Global Energy Management System in the Downstream and Chemical businesses, and our Production Operations Energy Management System in our Upstream businesses to identify and act on energy savings opportunities.

ExxonMobil is the most energy efficient refining company in the United States and internationally. The company has achieved a 10 percent improvement in energy efficiency across its global refining operations following an effort launched in 2000. ExxonMobil refining operations ranked in the first quartile for energy efficiency in every Solomon Refining Industry Survey over the past decade. Advanced efficiency technologies and techniques have helped ExxonMobil’s chemical business reduce its net greenhouse gas emissions intensity by nearly 7 percent since 2013. Through company-wide efforts, ExxonMobil expects to further improve our industry-leading energy efficiency in refining and chemical manufacturing facilities. 


Cogeneration is the simultaneous production of electricity while capturing useful heat or steam for industrial processes. By capturing and using energy that would have been lost as waste heat, cogeneration leads to increased energy efficiency and reduced greenhouse gas emissions. Cogeneration has been a significant factor in improving energy efficiency at ExxonMobil facilities around the world. 

We have interests in approximately 5,400 megawatts of cogeneration capacity in more than 100 installations around the world. This capacity is equivalent to the annual energy needed to power 2.5 million U.S. homes. Our cogeneration facilities enable the avoidance of approximately 6 million metric tons per year of greenhouse gas emissions. Over the past decade, we have added more than 1,000 megawatts of cogeneration capacity and continue to develop additional investment opportunities

Photo — ExxonMobil employees conducting an equipment check at the ExxonMobil refinery in Jurong, Singapore. 


Flaring is the process of burning gas as an alternative to releasing the gases directly into the atmosphere. Flaring is done for safety reasons or because the gas cannot be used due to barriers to the development of gas markets and gas infrastructure.

ExxonMobil is a charter member of the Global Gas Flaring Reduction Partnership, an initiative of the World Bank. This initiative seeks to reduce flaring by increasing the use of natural gas associated with oil production, helping remove technical and regulatory barriers to flaring reduction, conducting research, disseminating best practices and developing regulatory country-specific gas flaring reduction programs. Our Upstream Flaring and Venting Reduction Environmental Standard for Projects has a goal of avoiding routine flaring in new Upstream projects and to reduce flaring in our existing operations.

In 2017, flaring from our combined Upstream, Downstream and Chemical operations totaled 3.8 million metric tons. This represents a decrease of 1.2 million metric tons compared with our 2016 performance. This decrease was largely due to the restart of a third-party liquid natural gas plant in Angola. Further efforts associated with oil and gas production and processing are expected to lower natural gas flaring across ExxonMobil operations by about 25 percent by 2020 compared with 2016.

Chart — In 2017, flaring volume from our combined Upstream, Downstream and Chemical operations totaled 3.8 million metric tons. This represents a decrease of 1.2 million metric tons compared with our 2016 performance. 

Venting and fugitive emissions

Venting is the process of releasing methane and other gases into the atmosphere. Fugitive emissions occur when gases or vapors escape from pressurized equipment. We recognize the importance of reducing these emissions and are continuing to implement cost-effective methods to reduce methane and other hydrocarbon emissions in our operations. 

As part of our commitment to reduce methane emissions, in 2017, we joined an industry environmental partnership with the American Petroleum Institute focused on reducing methane and volatile organic compound emissions. The environmental partnership is made up of 25 natural gas and oil producers, including ExxonMobil. Participating companies will begin implementing the voluntary program starting in 2018 in an effort to further improve our environmental performance.

ExxonMobil, along with BP, Eni, Repsol, Royal Dutch Shell, Statoil, Total and Wintershall, has also committed to further reduce methane emissions across the natural gas value chain — from production to the final consumer. The eight energy companies issued Guiding Principles which provide a framework for continually reducing methane emissions, improving accuracy of methane emissions data and advocating sound policies and regulations on methane emissions.

The Guiding Principles were developed in collaboration with the Environmental Defense Fund, the International Energy Agency, the International Gas Union, the Oil and Gas Climate Initiative Climate Investments, the Rocky Mountain Institute, the Sustainable Gas Institute, The Energy and Resources Institute and United Nations Environment.

Our methane reduction efforts include structured leak detection and repair programs in which we use optical gas imaging cameras to identify leaks for prompt repair. We continue to replace high-bleed pneumatic devices with lower-emission technology and conduct reduced emissions completions in our ongoing efforts to enhance the environmental performance of our operations.

In 2017, our methane emissions totaled 7 million CO2-equivalent metric tons, which is similar to our performance over the last several years. Most of our venting and fugitive emissions are methane, which represents approximately 6 percent of our direct greenhouse gas emissions. Combined with additional measures outside the U.S. focused on the most significant sources of methane, ExxonMobil expects to achieve a 15 percent reduction of methane emissions by 2020 compared with 2016. 

Related content

Providing solutions for customers

Over the next few decades, population and income growth — and an unprecedented expansion of the global middle class — are expected to create new demands for energy and hydrocarbon-based products.

Sustainability Report

Spotlight: Taking action to manage methane emissions

In 2017, ExxonMobil and our subsidiary XTO Energy established a methane management program to reduce emissions of this greenhouse gas.

Sustainability Report

ExxonMobil and Sustainability

ExxonMobil’s primary responsibility is to produce the energy and products the world needs in a responsible manner.

Sustainability Report

Report archive

Download past versions of our Corporate Citizenship Report and External Sustainability Advisory Panel (ESAP) statements.

Sustainability Report

ExxonMobil supplier vendor and contractor expectations

ExxonMobil holds its suppliers, vendors and contractors to stringent compliance, anti-corruption, nonconflict, safety and other guidelines in order to stay in good standing.

Sustainability Report