Fugitive Emissions: An Explainer Guide

What Are Fugitive Emissions?

Fugitive emissions are the accidental leakage of greenhouse gases (GHG) from faulty infrastructure and equipment that transports fossil fuels.

Unfortunately, fugitive emissions are an important topic that doesn't get the exposure it deserves.  With an estimated 5% of global GHG emissions coming from fugitive emissions, you would think that fixing faulty fossil fuel equipment would be low-hanging fruit in the fight against climate change. But, due to the difficulty in detecting leaks at every fossil fuel facility's thousands of valves and tanks, fugitive emissions are difficult to calculate, grossly underestimated, and are considered a blind spot in global emissions reduction plans.  

Companies often overlook fugitive emissions due to the difficulty in measuring and calculating them. However, to understand the full extent of a company's emissions, they should be included in an emissions inventory when significant.

Examples of Fugitive Emissions

Fugitive emissions are caused by defective equipment, such as valves and pipes, and the migration of gasses from faulty fossil fuel wells or mines. The primary way fugitive emissions escape is from the extraction and transport of oil and gas. However, the extraction and transport of coal also release methane. One recent and high-profile example of leakage came from the Nord Stream pipelines, which flow liquified natural gas (LNG) from Russia to Europe. The three leaks in the pipelines were estimated to have leaked as much as 500,000 tonnes of methane.

Is Gas Flaring a Fugitive Emission?

Gas flaring is the burning of released pressurized gas for safety reasons and to reduce the amount of methane being emitted by an oil and gas facility, and is considered by some an example of fugitive emissions. However, because of the differences inherent in measuring and reducing emissions from faulty equipment vs. gas flaring, most companies measure and report gas flaring and fugitive emissions separately, and have different mitigation strategies to reduce them.

Is Methane a Fugitive Emission?

While carbon dioxide (CO2) and nitrous oxide (N2O) make up a small portion of fugitive emissions, methane is the predominant gas in these emissions. Methane is a powerful GHG with a global warming potential: On a 100-year timescale, methane has 28 times greater global warming potential than carbon dioxide and is 84 times more potent on a 20-year timescale. This means that one tonne of methane can considered to be equivalent to 28 tonnes of CO2 if looking at its impact over 100 years.

Fugitive Emissions in Oil & Gas

In 2016, the oil and gas industry was responsible for 85% of all fugitive emissions. The other 15% were from the coal sector, and a fraction of one percent came from industry. Fugitive emissions contribute a significant amount to oil and gas companies' scope 1 emissions. Two of the world’s largest oil and gas companies, Exxon Mobil and BP, cite the reduction of fugitive emissions as one of the primary means to reduce their total emissions. BP managed to reduce its air emissions by 38% from 2020 to 2021 by reducing fugitive emissions.

Some of the largest companies in the oil and gas industry, in early 2022, started the Aiming for Zero Methane Emissions Initiative. The signatories of the initiative have the ambitious target of eliminating methane emissions from the sector by 2030. Fugitive emissions are one of the oil and gas industries' main sources of methane emissions. The members of the group believe they can reduce fugitive emissions to zero through improved technologies for monitoring and mitigating.

How Are Fugitive Emissions Measured?

Fugitive emissions are measured on a case-by-case basis, based on the number of emissions that a source is estimated to produce, the difficulty of collecting data, and the local regulations surrounding the measurement and reporting of scope 1 facility emissions. The IPCC describes a three-tier approach to measuring fugitive emissions:

• Tier 1: Top-down Average Emission Factor Approach: This method is the simplest and most reliable method. It is a top-down approach that looks at which average production-based emission factors are applied to the reported volume of oil and gas production. This method should be used in regions with small amounts of oil and gas production where access to data is limited.
• Tier 2: Mass Balance Approach: The mass balance approach is used to measure flared gas emissions. It is called the mass balance approach because it takes into account the number of associated emissions balanced against the amount that is re-injected or re-used to calculate the amount that is flared off.
• Tier 3: Rigorous Bottom-up Approach: This is the bottom-up approach to measuring emissions that require in-depth infrastructure data and detailed production accounting data, and can include data directly from the actual measurement of emissions which is then aggregated at the facility level.

Fugitive emissions should be accounted for at both the facility and supply chain levels. The tier used for each facility and supply chain should be commensurate to the number of fugitive emissions they release. For fugitive emissions, only Tier 1 and 3 are relevant, as Tier 2 relates more to flared emissions. For fugitive emissions with low levels of emissions Tier 1 should be used, and for those with high emissions should use Tier 3.

Environmental Protection Agency (EPA) GHG Reporting Program

For US companies monitoring and annual reporting of fugitive emissions data is required under the EPA’s GHG Reporting Program at any oil and gas facility that emits more than 25,000 tonnes of CO2e. The requirements for detecting, reporting, and mitigating fugitive emissions are described in the EPA’s GHG Reporting Program SubPart W.

Under SubPart W oil and gas facilities have specific guidance for the monitoring, measuring, and remediation of fugitive emissions. Each facility is required to monitor for leak detections using verified gas imaging equipment that meet the specifications needed to detect fugitive emissions. Remediation of a detected leak must be attempted no later than 30 days after detection and is only considered repaired when no gas is detected from the gas imaging equipment. All of the monitoring, leak detections, and emissions data, have to be recorded and reported in an annual report.

How to Reduce Fugitive Emissions?

Fugitive emissions are a waste of fossil fuels; reducing them would save energy and money and help companies reach net zero targets. Making the reductions needed to eliminate fugitive emissions globally would require stricter regulations, investments in equipment, quality checks, and new processes.

Monitoring suspected leakage sites within the oil and gas infrastructure are essential for managing and reducing fugitive emissions. With so many areas of possible leakage and with many oil and gas facilities in remote areas with little human supervision, this task can be daunting, so companies prioritize monitoring activities in areas most likely to leak. Valves, for instance, are estimated to cause 60% of leaks. Therefore they make a great starting point while companies build out more advanced emission detection procedures over time. BP managed to reduce its fugitive emissions leak rate by 30% by installing a leak detection and repair system for 80,000 of its valves in a facility in Indiana.

To enable oil and gas companies to detect leaks at low costs, and help them to reduce their fugitive emissions, Project Canary has developed a self-sustaining continuous environmental monitoring system to detect leaks from defective oil and gas infrastructure. The system updates every second and can detect even small amounts of methane for small or intermittent leakage. Giving oil and gas companies the ability to view their operations in real time and quickly detect and remediate leaks at a fraction of the cost of other methods.

Most oil and gas companies are now getting to grip on their scope 1 emissions with new technologies for detecting, measuring, and mitigating the whole extent of their fugitive emissions and regulatory pressures like the EPA’s GHG Reporting Program ensuring oil and gas facilities are required to disclose fugitive emissions data. Persefoni can help those companies upload, visualize, and track their scope 1 emissions by each facility. But for oil and gas companies looking to measure their entire carbon footprint, including scope 3 emissions, which accounts for an average of 88% of the oil and gas sector’s emissions, Persefoni, can help companies measure, manage, and report those emissions. To find out how Persefoni can help oil and gas companies measure the full extent of their carbon footprint, reach out for a demo.