After CO2, methane is the main cause of global warming. The fact that the amount of methane has increased more than expected since 2007 is therefore downright bad news. So what is it exactly that has caused this rise? That's still a bit of guesswork. All the more reason, therefore, to map out methane emissions as accurately as possible. TNO is one of the parties that is working on this.
Would you like to know more about TNO's research on methane emissions? Please contact Hugo Denier van der Gon.
Methane enters our atmosphere in different ways. Through cows, for example. In fact, livestock farming is the largest source of methane emissions in the Netherlands. Methane also seeps out from swampy areas and escapes from ocean floors. In addition to these natural emissions of methane, the oil and gas industry in particular plays a major role in the emission of this greenhouse gas. Methane is the primary component of natural gas and during the production and distribution of oil and gas, methane may leak to the atmosphere. For a long time, that was an underrated problem. It was only when the US began to take measurements in areas where shale gas is extracted that it became clear that significantly more methane was leaking than had been expected.
“Methane is responsible for some 20 to 30 percent of global warming”
About 30 times stronger than CO2
"We're really talking about a powerful greenhouse gas," emphasises Hugo Denier van der Gon, Senior Scientist Climate, Air and Sustainability at TNO. "Estimates vary, but methane as a greenhouse gas is about thirty times stronger than CO2. Worldwide, however, much less methane than CO2 is released into the atmosphere. Nevertheless, methane is responsible for some 20-30% of global warming. The tricky thing about these estimates is that we have very little measurement data at our disposal. As a result, we don't know exactly how big the problem is and we also don't know exactly what the precise emissions of the different methane sources are."
Large-scale measurement campaign
More, and more accurate, measurements, that’s the maxim. And that is exactly what TNO and other parties did last October during a three-week measurement campaign in Romania. "This was done through a large consortium, involving as many as 30 people taking measurements. We took measurements in various Romanian oil and gas areas. Two planes also flew over those areas," says Denier van der Gon.
“Thanks to our Quantum Cascade Laser, we can find out whether we are dealing with natural gas methane or not”
"TNO drove around in a truck with a Quantum Cascade Laser (QCL), a special instrument with which we can measure methane and ethane very accurately. Natural gas consists mostly of methane, but also contains some ethane. There is no ethane released from agriculture and livestock. Thanks to our QCL, we can find out whether or not we are dealing with methane from natural gas."
"Now that all the measurements are in, the real work is only just beginning," continues Denier van der Gon. "We are still working until February 2020 to get everything right. There are a lot of factors involved, so it's definitely not a matter of just pushing a button. In order to determine the actual emissions, we need to look not only at the measured amount of methane, but also, for example, at the distance to the source and wind speed at the time of the measurement. We are also grateful that we can use Tropomi, a satellite that can map the air pollution in an area of seven kilometres by seven.”
“If we get a better view of methane leakages worldwide, the oil and gas industry can take mitigating measures”
The TNO measurement campaign in Romania is being financed for the most part by the European Commission. The Oil & Gas Methane Partnership (OGMP), a partnership in which companies such as Shell, BP and Total are involved, is also making a financial contribution through the Climate and Clean Air Coalition (CCAC) international methane science studies, administered through the United Nations Environment Program. "Both politicians and the oil and gas industry realise how important it is to get a clear picture of methane emissions," concludes Denier van der Gon. "This is, of course, mainly due to the Paris Climate Agreement. It would be good if we could soon gain more insight into methane leakages worldwide, so that companies in the oil and gas industry can take mitigating measures. They can then simply sell that methane-rich natural gas and at the same time ensure that this methane does not become a greenhouse gas in our atmosphere. If that's not a win-win, I don’t know what is."