In Plane Sight: How to measure methane leaks
30 November 2021
At the UN’s climate change summit in Glasgow earlier this month, diplomats and dignitaries from more than a hundred countries signed a historic pledge to cut global methane emissions by 30% in the next decade. If we are to do so, however, we must first understand the scale of the problem. In a previous article in this series, we looked at how our inability to estimate methane emissions means we must instead measure them. In this article, we look at how that measurement can now be done, with greater accuracy than ever before.
Until recently, detecting methane leaks was near impossible. As the main constituent of natural gas, methane routinely escapes from rickety pipes and valves in the oil and gas sector. Just a decade ago, the process of finding these leaks was laborious. To do so, infrared cameras were mounted on trucks which navigated thousands of miles of remote desert, arctic tundra, or sprawling webs of pipeline. Offshore emissions, meanwhile, often went undetected entirely.
New technology has changed the picture. Today, we have eyes in the sky. In the past decade, a cluster of start-ups have attached methane sensors to satellites, planes, and drones. With these platforms, we can now accurately detect and locate emissions from above. Once leaks are found, they can then be fixed – either by burning the methane as it is released, or by simply repairing the source of the leak.
The question is which tool to use and when, and it is a question of scale.
Satellites
On informing operators and getting leaks fixed: “To us, that was a perfect example of the power of satellite monitoring, and how we can make a substantial contribution to the fight against climate change.” says President Stéphane Germain.
To know where major leaks are, anywhere in the world and at any moment, we need satellites. Orbiting the earth in just a few hours, satellites can spot large plumes of methane from space.
They are doing so constantly. Wherever you are in the world today, look upwards at 1:30pm. Sentinel 5P, a European Space Agency satellite, is measuring methane emissions, at a height of 800km, directly above you.[1]
Satellite data has confirmed what scientists had long suspected. Oil and gas equipment has been leaking methane into the atmosphere, at a rate of thousands of kilograms every hour, without detection, for decades. Seventy million tonnes are believed to escape each year.[2] Now, thanks to infrared cameras at dizzying heights, we can pinpoint the sources of these emissions.
In 2016, GHGSat, a Canadian start-up, launched “Claire”, its pilot satellite. The first emissions source it detected was an epic plume coming from a gas facility in Turkmenistan. Each year, the warming impact of that single source was equivalent to the exhaust of one million cars, and it had been leaking for years.
Confirming its findings with the European Space Agency, GHGSat was able to inform the operator and get the leak fixed. “To us, that was a perfect example of the power of satellite monitoring,” says President Stéphane Germain, “and how we can make a substantial contribution to the fight against climate change”.
Planes
“In the last few years alone, [Kairos Aerospace] has had more impact on greenhouse gases than every Tesla vehicle ever made.” says CEO Steve Deiker.
Not all emissions can be seen from space, however. There is a long tail of much smaller leaks. To spot these, we can use planes. At an altitude of just over 900 meters, aircraft can detect methane emissions that are up to ten times smaller than those visible to satellites.[3]
One such company, Kairos Aerospace, surveys up to 100 square miles a day per plane.[4] It attaches methane spectrometers, about the size of a briefcase, to the wing struts of light aircraft. They then soar over vast oil basins, measuring which equipment is leaking. And with at least 3 million miles of gas pipeline in the US alone, its data helps companies prioritise which leaks to tackle first.[5]
The name, Kairos, is fitting. “Kairos is a Greek word,” explains Steve Deiker, the company’s founder. “It essentially means the opportune time to do something.” To date, Kairos Aerospace has helped the oil and gas industry remove at least 30 billion cubic feet of methane from the atmosphere – equivalent to roughly 15 million tonnes of carbon dioxide. Its monitoring “in the last few years alone,” Deiker notes, has had “more impact on greenhouse gases than every Tesla vehicle ever made”.
Drones
CEO of SeekOps, Iain Cooper, cites Stanford Professor Adam Brandt in comparing today’s advances in methane detection to the nineteenth century gold rush. “In the early days, the big nuggets were found first, these are the big leaks”. He then explains. “And then you get more sophisticated in getting the little nuggets out, and there are many of those – these are the long tail of emissions”.
There are several cases when planes make way for “sniffer” sensors mounted on drones. Drones can locate the very smallest pinhole leaks at wells and extraction sites. They can even tell when a gas cooker has been left on. They can also operate over water, swamps, and in rain and fog where other remote sensing devices are ineffective.
Iain Cooper, CEO of SeekOps, cites Stanford Professor Adam Brandt in comparing today’s advances in methane detection to the nineteenth century gold rush. “In the early days, the big nuggets were found first, these are the big leaks”. He then explains. “And then you get more sophisticated in getting the little nuggets out, and there are many of those – these are the long tail of emissions”. Cooper’s company, a spinoff from NASA’s jet propulsion laboratory, is proof of the sophistication of methane leak detection today. Unlike the infrared sensors attached to planes and satellites, SeekOps use highly sensitive miniaturized methane sensors, which were originally designed to detect methane on NASA’s Mars rover project. They have a very low detection threshold with parts per billion sensitivity. And small leaks are common: SeekOps has never surveyed a well site that wasn’t leaking to some degree.
Perhaps the biggest breakthrough, however, has been the use of drones at offshore rigs. For the past few years, bp has been working with SeekOps to verify its estimated methane emissions from assets in the North Sea. Unmanned drones are deployed from the nearby coast of the Shetland Islands, and flown to offshore rigs over 75 kilometres away. Each flight can log up to 100,000 individual methane readings in under an hour. Previously, this kind of operation would require a supply boat, a helicopter, or a standby vessel. Now, bp is planning to deploy specialist drones to many more of its offshore assets.[6]
Climate Investments’ role
The range of options available to measure methane is their strength. “No technology is a silver bullet,” notes GHGSat’s Stéphane Germain, “ultimately the right answer is to use a combination of all those technologies to get the most efficient and cost-effective service”.
With one technology alone, finding leaks can be challenging. Satellites struggle with offshore sites, as bodies of water absorb infrared light. Planes are restricted by access to airspace and need daylight. Drones, while precise, cover less area per day than aircraft. Then there is the biggest uncertainty of all methane monitoring: wind. No existing leak detection technology can match a stormy day. “You just need to stand in your backyard for half an hour to see how many times the wind can change direction,” says Germain. “You wind up having plumes that are shaped like spaghetti noodles”.
Yet leak detection is improving constantly. The benefit can be commercial too. Triple Crown, a small energy company in the Permian Basin, hired Kairos Aerospace a year ago to monitor methane from its oil wells. Its report on the economics of repairing leaks – weighing the cost of fixing leaks against the sale price of the gas conserved – found that aerial leak detection paid back in just five days.
The vast majority of majors, super majors, and several national companies have tested aerial monitoring at their sites. “The challenge now is to accept it in operations – to move from an R&D project to using this on a daily basis” says Germain. “Large organisations of hundreds of thousands of people have to think a little differently about how they do business”. If the oil and gas industry is to meet the challenge of rapidly reducing methane emissions, then using these technologies at scale is an essential and urgent first step.
For OGCI Climate Investments, the solution is to invest widely in the leak detection ecosystem. Whether it’s drones hovering just meters above us, planes patrolling the skies, or satellites tracking emissions from space, OGCI Climate Investments is at the forefront of this energy transformation, backing companies and products that can make a lasting difference.
Detecting leaks has never been easier. The question now is: how can leaks be prevented in the first place? Our next article will explore the infrastructure designed to eliminate leaks altogether, and what the future could hold for the oil and gas sector.
