The case for stopping methane leakage

Carbon dioxide is not the only greenhouse gas. Methane, though relatively short-lived, is a much more potent global warming pollutant, with emissions of it from the natural gas supply chain suspected of being vastly underestimated. Regulation is urgently needed to deal with the growing problem, say experts

PROBLEMS Methane emissions from manmade sources, including the oil and gas industry, are rising. The gas is 120 times more potent than carbon dioxide kilo for kilo when emitted and some 80 times more potent over the first 20 years after it is emitted. It accounts for more than 25% of the warming the world is experiencing

SOLUTIONS Better measurement by satellites to fully understand the scale of the problem and regulation to ensure urgent action is taken

KEY QUOTE “A 45% reduction in oil and gas methane emissions by 2025 would deliver the same 20-year climate benefit as closing one-third of the world’s coal-fired power plants.”

Carbon dioxide is the greenhouse gas on the tip of everyone’s tongue. Methane is its more obscure cousin and generally associated with flatulence from intensively farmed dairy cows. But farting cattle are not the only source of methane. The oil and gas industries are also responsible for vast amounts of methane emissions and experts increasingly believe that official statistics drastically underestimate the scale of the issue. Methane emissions have increased by about 25 teragrams (Tg) (equal to one trillion grams) a year since 2006. Research by NASA suggests about 17 Tg a year of that increase is due to fossil fuels. This is a big worry given that gas is frequently heralded as a key part of global emissions reduction strategies and a vastly cleaner option than coal.

Unlike carbon dioxide (CO2), which once released sticks around in the atmosphere for over a century, methane (CH4) is a short-lived climate pollutant, taking around a decade to break down. It is, however, 120 times more potent than carbon dioxide kilo for kilo when emitted and some 80 times more potent over the first 20 years after it is emitted. Methane from manmade sources accounts for more than 25% of the warming we are experiencing, estimates the Intergovernmental Panel on Climate Change (IPCC). The International Energy Agency (IEA) in its 2017 World Energy Outlook concludes that the concentration of methane in the atmosphere is currently around two-and-half times greater than pre-industrial levels.

In 2012, the latest year for which comprehensive data are available, global methane emissions were estimated to be around 570 million tonnes, around 40% from natural sources and the remaining 60% from anthropogenic sources, says the IEA. The Environmental Defense Fund (EDF), a non-profit, believes figures are much higher. Its work in the US suggests real-world methane emissions from the natural gas supply chain are around 60% higher than those published by the US Environmental Protection Agency because of “outdated reporting requirements and modelling formulae”. EDF includes methane emissions along the whole of the gas supply chain, including production sites, transport and storage and delivery, but not those associated with end use. “We do not have good enough empirical data to make solid estimates at this time for total end-use emissions,” says Steven Hamburg, chief scientist at the NGO.

EDF drew its conclusions after studying more than 40 recently published scientific papers covering one-third of US natural gas supply. Discrepancies with official data are most startling in the drilling and production phase and proportionally smaller further downstream, though EDF is revising local distribution estimates with additional data, says Hamburg. Similar patterns are likely to emerge in other countries as “inventories based on emission factors derived from engineering studies are biased low”, says Hamburg, adding that such studies “underlie almost all inventories”. Ongoing studies will show how often this is actually the case, he adds.

INDUSTRY VOLUNTARY AGREEMENT

The primary component of natural gas is methane and gas leaks occur throughout the supply chain. Since most oil wells also produce natural gas, the extraction of oil can increase methane emissions. “Leaks can occur at all stages of the supply chain, including production, processing, long distance transmission and local distribution,” states a report from the University of Pennsylvania. “Some leaks occur when underground pipelines corrode, others occur at surface equipment and still others occur when gas is intentionally vented during maintenance tasks. Detecting and measuring leaks is hard, since methane is odourless and colourless.”

The IEA says there is no excuse for any country not to tackle the methane leakage problem. “The technologies and approaches to address methane emissions from the oil and gas sector are available already today and there is a growing number of voluntary and regulatory efforts in this area,” it states.

One of the main voluntary agreements is the Oil and Gas Climate Initiative (OGCI), led by 13 oil and gas companies, including BP, Chevron, ExxonMobil, Shell and Total, and aimed at reducing greenhouse gas emissions. In September 2018, it agreed to reduce by 2025 its collective average methane intensity — the methane lost in the atmosphere when producing oil and gas as a percentage of the gas sold — by one-fifth to below 0.25%, with the ambition to get to 0.20% or a reduction of one-third. EDF believes a 45% cut globally in methane emissions is needed by 2025.

The OGCI target does not include the methane emissions of Chevron, Exxon Mobil and Occidental Petroleum, three US majors that together represent 5% of global oil and gas production, since they joined the initiative after the agreement was drawn up. Exxon Mobil announced plans in May 2018 to reduce methane emissions by 15% by 2020. Jérôme Schmitt, chair of OGCI’s executive committee, insists that: “Supporting the intensity target and ambition is a requirement for all new members.” OGCI says it would like to see “near zero methane emissions from the full gas value chain”, but that it can only “influence” parts it does not own or control, such as transport and distribution to final customers.

REGULATION NEEDED

Many experts believe only regulation will ensure the necessary action is taken quickly. “Although companies would, in most cases, prefer not to waste methane, leaks are commonplace because—from a company’s perspective—they are not always cost-effective to prevent or to fix once they occur,” say the University of Pennsylvania researchers. “Voluntary targets set by companies… do not come with the financial incentive that guarantees sufficient emissions abatement” and hence regulation is needed to enforce the necessary change, they conclude.

Environmental NGOs and green politicians in Europe are also keen to see action by regulators. The Greens in the European Parliament published a paper in spring 2019 asking EU member states and the European Commission to take the Paris Climate Agreement fully into account when discussing plans for the future of gas. The EU executive body is currently preparing measures for the EU gas market and the next Commission, due to take office in November 2019, is expected to issue a regulatory gas package. Further, the EU Energy Union governance requires the Commission to come forward with a methane strategy before 1 January 2020.

EDF began its campaign on methane emissions in the US, but is turning its attention to the EU where it believes a similar problem of measurement exists and where it might be easier to influence policy makers and drive large-scale change. “We are working to implement regulation,” says Poppy Kalesi, EDF’s Europe-based policy director, but admits it is an uphill struggle because methane remains under the radar compared to CO2 and because, in the US, of the incumbent President’s anti-environmental stance. “Federal regulations are being rolled back by the Trump administration and we are spending lots of time simply stopping this,” adds Kalesi. President Trump is expected before summer 2019 to issue a proposal aimed at eliminating the direct regulation of methane emissions from oil and gas facilities. This follows previous proposals by his administration to weaken efforts to reduce methane pollution from these plants.

“The EU, compared with the US and other countries, is a role model regarding climate and more operational procedures regarding carbon dioxide reduction,” says Kalesi. “European oil and gas companies tend to have better practices and to bring their standards into other regions where they work. This gives them more leverage to engage in a positive way in all countries.” She highlights the Commission’s State of the Energy Union report from April 2019 as proof that things are changing. It explicitly highlights the satellite monitoring of carbon dioxide and methane emissions as critical to designing better energy and climate policies and could be “a game changer” in how gas is seen in the EU, believes Kalesi. “It is the responsibility of the EU institutions and national governments to ensure Europe plays its part in cutting global methane emissions. This includes supplies to the EU, upstream and end uses,” she says.

SATELLITE MEASURING

The Commission says it is ”very actively looking into the issue of methane reduction across the field”. The Joint Research Centre, the Commission’s science and knowledge hub, cites a number of reports it has published on the issue looking at monitoring and modelling to verify greenhouse gas inventories, its emissions database that shows methane emissions worldwide for all anthropogenic sectors. Under Horizon2020, an EU research programme, the Commission is funding the VERIFY project, which seeks to develop a system to estimate greenhouse gas emissions, including methane, to help countries report accurately to the UN Climate Change Convention secretariat. The EU executive also plans to launch a study on intra-EU methane emissions.

Action to reduce methane emissions at a global level is led by the Climate and Clean Air Coalition (CCAC), a voluntary partnership of governments, intergovernmental organisations, businesses, scientific institutions and civil society organisations, of which the Commission is a member, and initiatives under the auspices of UN Environment. EDF is working with CCAC to measure methane emissions from the production of liquefied natural gas (LNG) and from offshore activity in the North Sea. The EU currently monitors atmospheric methane via the satellite Copernicus Sentinel 5. But it does not systematically measure methane at local or ground level and the Commission admits Russia and the US have more advanced systems.

In 2021, EDF plans to launch its own satellite, MethaneSAT, to fill this gap. MethaneSAT will reveal global, high-resolution methane emissions from oil and gas facilities worldwide “exceeding anything in orbit or on the drawing board today”, says the organisation. And because it will focus only on methane, it will be “quicker and less expensive to launch than the complex, multi-function satellites built by government space agencies, so we can get data sooner,” insists EDF.

Cutting methane emissions not only makes good climate sense, but also good business sense. Leakage of any sort is rarely economically intelligent and the IEA suggests that in many cases “there is a readily available path to market for the captured methane to be sold”. It states: “If the value of this methane is greater than the cost of the technology to capture it, it would be possible to avoid the emissions of a potent greenhouse gas while simultaneously generating a profit.” The IEA estimates that around 40-50% of methane emissions could be avoided at no net cost and that in all regions of the world “reducing oil and gas methane emissions remains a cost-efficient way of reducing greenhouse gas emissions compared with other mitigation strategies”.

For EDF, being able to measure the scale of the methane problem, pinpoint the leaks and better understand where the biggest potential reductions can be made is key to solving the problem. This is why MethaneSAT is so important. ”I expect this to transform how we talk about and understand the role of gas in the EU as well as in the rest of the world,” says Kalesi. “A 45% reduction in oil and gas methane emissions by 2025 would deliver the same 20-year climate benefit as closing one-third of the world’s coal-fired power plants,” she states.

TEXT Philippa Nuttall Jones

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