Methane: Tackling a rising climate priority

Here’s a quick quiz question on emissions: what is the biggest contributor to climate change after CO₂?

The answer is methane, which accounts for 11% of global emissions and is responsible for about 30% of the rise in global temperatures since the Industrial Revolution.

Reducing methane is “low-hanging fruit” in the race to tackle climate change, according to the United Nations Environment Programme (UNEP).

Yet atmospheric concentrations are rising more quickly than those of all other greenhouse gases. And unintentional leaks of methane from industrial equipment — also known as ‘fugitive emissions’ — are a sizeable part of the problem.

With natural gas — of which methane is the primary component — considered an important fuel for the energy transition, what are industries doing to address this rising priority?

Methane and climate change

Methane is a potent greenhouse gas (GHG) with a global warming potential of more than 80 times greater than CO₂ over the first 20 years after it reaches the atmosphere.

But whereas CO₂ hangs around for centuries, methane has a much shorter atmospheric lifespan of around 12 years. Experts say this means cutting methane emissions can help reduce temperature increases in the short term.

Doing so by 45% this decade can help keep global warming below 1.5°C, according to UNEP.

Focusing on emissions from the biggest sources will be key. While about 40% of methane emissions come from natural sources such as wetlands, the remaining 60% are created by humans.

The two largest anthropogenic sources are agriculture, which is responsible for about a quarter of methane emissions, and the energy sector, which produces one third, including emissions from coal, oil and natural gas.

The energy sector and methane leaks

Fossil fuel supply offers the greatest potential for immediate reductions in methane emissions, according to the latest Global Methane Tracker from the International Energy Agency (IEA).

Oil and gas are estimated to account for up to a quarter of anthropogenic methane emissions, contributing to the issue in a variety of ways.

Some, such as practices including venting and flaring that are performed for safety reasons or during maintenance, are intentional. Others are unintentional – primarily leakage that can often result from poor maintenance and broken equipment.

These incidents are sometimes referred to as ‘super-emitters’ because they can release huge amounts of methane.

A leak from one oil and gas facility in Turkmenistan was estimated to be 333 tonnes per hour at its peak — equivalent to the GHG emissions of a car driving for 38,000 miles.

Research has found evidence of thousands of super-emitter events per year across the globe.

What is being done about methane leaks?

Methane can leak anywhere along the gas supply chain, from upstream at the wellhead and processing plant to downstream through pipelines and distribution lines.

Addressing the problem starts with detection. Here, a range of technologies are being deployed.

Oil and gas companies are using optical gas imaging cameras in leak detection and repair programs. Such equipment, which uses infrared technology to visualize otherwise invisible leaks, is capable of scanning thousands of components to pinpoint leaks which can be repaired almost immediately.

Others are using drones equipped with sensors that can detect methane emissions and identify their source at both onshore and offshore facilities.

There are also a growing number of methane-detecting satellites orbiting Earth. A NASA program monitoring super-emitters from space, for example, found more than 50 sites emitting high rates of methane across central Asia, the Middle East and southwestern United States.

Efforts are also being made to address methane emissions from downstream operations, such as transmission, storage and distribution, which are responsible for about 15% of methane emissions from oil and gas, although this figure grows higher in major importing countries such as some European Union member states and Japan.

In the maritime industry, Mitsubishi Heavy Industries (MHI) Group is developing a methane oxidation system for LNG-fueled marine engines that, in testing, has shown a 70% reduction in escaped methane. Such technology could help the sector achieve its goal of reducing GHG emissions to net zero by 2050.

A significant opportunity

While experts say there is still a long way to go to address methane emissions, many countries and companies are looking to improve their methane reporting. And over 150 countries have signed a Global Methane Pledge to cut collective methane emissions by 30% by 2030, compared to 2020 levels.

The economic benefits to doing so are estimated to be sizeable — limiting methane emissions could make nearly 100 billion cubic meters of natural gas available to markets, according to the IEA.

The environmental benefits promise to be significant, too. Deploying targeted methane mitigation solutions in the fossil fuel sector could, by 2050, have an impact comparable to eliminating all CO₂ emissions from the globe’s heavy industry.