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Mitigating greenhouse gas 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 continuing to take actions to mitigate greenhouse gas emissions within our operations.

ExxonMobil has a robust set of processes designed to improve efficiency, reduce emissions and contribute to effective long-term solutions to manage climate change risks. These processes include, where appropriate, setting tailored objectives at the business, site and equipment levels, and then stewarding progress toward meeting those objectives. Based on decades of experience, ExxonMobil believes this rigorous bottom-up approach is a more effective and meaningful way to drive efficiency improvement and greenhouse gas emissions reduction than simply setting high-level corporate targets. We also believe that continuing to use this approach will yield further improvements in all sectors of our business.

In the near term, we are working to increase energy efficiency while reducing flaring, venting and fugitive emissions in our operations. In the medium term, we are deploying proven technologies such as cogeneration and carbon capture and sequestration where technically and economically feasible. Longer term, we are conducting and supporting research to develop breakthrough, game-changing technologies. Since 2000, ExxonMobil has spent approximately $7 billion to develop lower-emission energy solutions.

In 2015, ExxonMobil’s net equity greenhouse gas emissions were 122 million CO2-equivalent metric tons. Relative to our 2014 performance, our 2015 emissions decreased by approximately 1 million CO2-equivalent metric tons. This decrease was primarily driven by energy efficiency improvement and asset divestment.

Energy efficiency

In 2015, energy used in our operations totaled 1.7 billion gigajoules. Energy consumed in our operations generates more than 80 percent of our direct greenhouse gas emissions and is one of our largest operating costs. As such, we have focused on energy efficiency for several 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.

Through our commitment to energy efficiency, application of structured processes and continued use of a bottom-up approach, we continue to yield industry-leading results. For example, in the 2010, 2012 and 2014 Refining Industry Surveys3, ExxonMobil’s global refining operations achieved first quartile energy efficiency performance.

3The Solomon Survey provides a global benchmarking assessment of the refining industry and is conducted every two years.


In 2015, flaring volume from our combined Upstream, Downstream and Chemical operations totaled 5.3 million metric tons. This represents an increase of 0.8 million metric tons compared with our 2014 performance.

Chart — In 2015, flaring volume from our combined Upstream, Downstream and Chemical operations totaled 5.3 million metric tons. This represents an increase of 0.8 million metric tons compared with our 2014 performance.

The increase in flaring in 2015 was primarily due to operations in Angola, where a third-party-operated liquefied natural gas (LNG) plant was not operating. These increases were partially offset by flaring reductions resulting from the completion of commissioning work at our Papua New Guinea LNG plant and operational improvements at the Usan production field in Nigeria.

ExxonMobil is a charter member of the Global Gas Flaring Reduction Partnership. In addition, we put in place our own parameters, the Upstream Flaring and Venting Reduction Environmental Standard for Projects, in 2005. Accordingly, our goal is to responsibly avoid routine flaring in new Upstream projects and reduce “legacy” flaring in our existing operations.

For example, our joint venture operations in Qatar have recently begun using a jetty boil-off gas (JBOG) recovery facility to recover the natural gas that was previously flared during LNG vessel loading at the marine berths located at the Ras Laffan Port. Approximately 1 percent of the LNG loaded onto the ships evaporates due to the difference in temperature between the LNG and the ship tank. The JBOG recovery facility collects the boil-off gas and returns it to the LNG plants to be used as fuel or converted back into LNG. During one year of operation, the JBOG facility has recovered more than 500,000 metric tons of gas and reduced LNG vessel loading-related flaring by around 90 percent.

Venting and fugitive emissions

Our venting and fugitive emissions in 2015 totaled 6 million CO2-equivalent metric tons, which is essentially flat relative to our 2014 performance. While venting and fugitive emissions, most of which are methane, represent approximately 5 percent of our direct greenhouse gas emissions, we recognize the importance of reducing these emissions. We continue to look for cost-effective ways to reduce methane and other hydrocarbon emissions in our operations, such as replacing high-bleed pneumatic devices with lower-emission technology and conducting green well completions in targeted Upstream operations.

Up Close: Mitigating methane emissions at XTO Energy

XTO Energy manages methane emissions as a matter of safety and environmental responsibility. Responsible methane containment practices are applied during drilling, completion and production operations to minimize methane emissions. We manage emissions through a mix of voluntary and regulatory actions, such as implementing leak detection and repair programs, reducing oil and gas completion emissions and targeting replacement of high-bleed pneumatics with lower-emitting devices.

Photo — Paula Byrum inspects equipment at our XTO Energy operations site near Herbert Springs, Arkansas.

After drilling and completion of a new well, our workers prepare the production equipment for decades of operation. A key part of these preparations is to ensure that the natural gas product is contained by the production equipment. We utilize optical gas imaging cameras to locate equipment leaks that would otherwise be invisible, which allows us to detect leaks and make repairs. This attention to detail is important to promote safety and environmental performance.

There is a growing interest within the scientific and policy communities on human-related methane emissions. In the United States, we are working with federal and state governments and within industry to ensure that regulations aimed at reducing emissions of methane and volatile organic compounds sufficiently support long-term operations, achieve emission reduction objectives and provide flexibility for technology.

We continue to seek greater understanding of the magnitude and characteristics of oil and gas industry-related methane emissions. XTO Energy participated in studies conducted by the University of Texas and Environmental Defense Fund which quantified the methane leakage rate in the United States from Upstream gas production activities at 0.4 percent of the total gas produced. The results of this study helped validate Environmental Protection Agency estimates. We are active in ongoing methane research including participating in a methane measurement reconciliation study with the Department of Energy’s National Renewable Energy Laboratory to close the knowledge gap between methane measured at ground sources and methane measured from the air. We are also working with Stanford University on its new Natural Gas Initiative, which will focus on methane measurement and monitoring technologies.


Cogeneration technology captures heat generated from the production of electricity for use in production, refining and chemical processing operations. Due to its inherent energy efficiency, the use of cogeneration leads to reduced greenhouse gas emissions. Our cogeneration facilities alone enable the avoidance of approximately 6 million metric tons per year of greenhouse gas emissions.

We have interests in approximately 5,500 megawatts of cogeneration capacity in more than 100 installations at more than 30 locations around the world. This capacity is equivalent to the annual energy needed to power 2.5 million U.S. homes. Over the past decade, we have added more than 1,000 megawatts of cogeneration capacity and continue to develop additional investment opportunities.

For example, ExxonMobil began the construction of a new 84-megawatt cogeneration facility at our Singapore refinery’s Jurong site. When this facility is completed in 2017, ExxonMobil will have more than 440 megawatts of cogeneration capacity in Singapore, enabling our integrated refining and petrochemical complex to meet all its power needs.

Up Close: Managing the business risks of climate change

By 2040, the world’s population is projected to reach 9 billion — up from about 7.2 billion today — and global GDP will have more than doubled. As a result, we see global energy demand rising by about 25 percent from 2014 to 2040. In order to meet this demand, we believe all economic energy sources, including our existing hydrocarbon reserves, will be needed. We also believe that the transition of the global energy system to lower-emissions sources will take many decades due to its enormous scale, capital intensity and complexity. As such, we believe that none of our proven hydrocarbon reserves are, or will become, stranded.

Energy and Carbon Managing the Risks

ExxonMobil’s long-range annual forecast, The Outlook for Energy, examines energy supply and demand trends for approximately 100 countries, 15 demand sectors and 20 different energy types. The Outlook forms the foundation for the company’s business strategies and helps guide our investment decisions. In response to projected increases in global fuel and electricity demand, our 2016 Outlook estimates that global energy-related CO2 emissions will peak around 2030 and then begin to decline. A host of trends contribute to this downturn — including slowing population growth, maturing economies and a shift to cleaner fuels like natural gas and renewables — some voluntary and some the result of policy.

ExxonMobil addresses the potential for future climate change policy, including the potential for restrictions on emissions, by estimating a proxy cost of carbon. This cost, which in some geographies may approach $80 per ton by 2040, has been included in our Outlook for several years. This approach seeks to reflect potential policies governments may employ related to the exploration, development, production, transportation or use of carbon-based fuels. We believe our view on the potential for future policy action is realistic and by no means represents a “business-as-usual” case. We require all of our business lines to include, where appropriate, an estimate of greenhouse gas-related emissions costs in their economics when seeking funding for capital investments.

We evaluate potential investments and projects using a wide range of economic conditions and commodity prices. We apply prudent and substantial margins in our planning assumptions to help ensure competitive returns over a wide range of market conditions. We also financially stress test our investment opportunities, which provides an added margin against uncertainties, such as those related to technology development, costs, geopolitics, availability of required materials, services and labor. Stress testing further enables us to consider a wide range of market environments in our planning and investment process.