Challenge, opportunity as China begins to tackle fossil fuel methane emissions

By Hanling Yang and Stefan Schwietzke

Even as China races to reduce heat-trapping carbon dioxide (CO2) emissions and conventional air pollutants from across its growing economy, new concerns are arising over methane, an extremely potent greenhouse gas. The latest United Nations Intergovernmental Panel on Climate Change (UN IPCC) Special Report confirms that deep reductions in emissions of non-CO2 pollutants, particularly methane, are also essential to limiting warming to 1.5 degrees.

Among China’s top sources of methane emissions are coal, gas and oil operations, which also offer the quickest and most effective opportunities for reduction of this pollution. China has a huge opportunity to tackle methane from these sectors, but better accounting of these emissions is needed if government and industry are going to solve the problem.

Methane from coal

Methane is a potent greenhouse gas with more than 80 times the warming power of carbon dioxide over the first 20 years after it is released. Human-made methane emissions are responsible for more than a quarter of the warming we are experiencing today across the globe.

Methane emissions present a challenge across the fossil fuel sector. For example, although China is rapidly replacing coal with natural gas in order to reduce urban air pollution, coal still accounts for 60 percent of the primary energy China uses, and will remain a dominant fuel for decades to come.

A recently published study in Nature Communications used satellite data to explore whether regulatory efforts launched by the Chinese government in 2010 were effective in reducing methane emissions from coal mines. Regrettably, the data indicates the regulations are not working as hoped. Coal mine methane remains the driving force behind the significant rise in China’s annual methane emissions between 2000 and 2015, a total increase equivalent to the annual natural gas use of about 6 million US households.

The findings show differences in estimates of emissions between the satellite analysis and conventional “bottom-up” calculations based on emission factors. As the first scientific study using satellite observations to focus on China’s methane emissions, the insights of the paper highlight two urgent issues for China, which is believed to be the world’s largest man-made methane emitter.

More data, better numbers

First, the country needs to validate its methane emissions inventory by using direct, “top-down” measurements (such as drive-by and airborne methods) in tandem with “bottom-up” measurement methods. The list of available options for gathering the required data is growing by the month.

Second, China’s official methane strategy must expand to encompass climate and other environmental impacts, not just the immediate local safety concerns that regulators consider today. For example, coal mines are currently required to either capture or burn off (flare) any mine gases with a methane concentration greater than 30 percent, but mine emissions that fall below that threshold are exempt to avoid risks of explosions.

But compliance with mere safety standards leaves lots of methane escaping into the atmosphere, which not only has significant climate impacts but could also affect air quality. About 90 percent of China’s coal mine methane emissions — approximately 20 billion cubic meters — occur at concentrations below 30 percent, leaving them exempt from the regulation.¹

Moreover, while China has mandatory emissions reduction and peaking targets for carbon dioxide, there are no similar mandates for methane.

Methane from oil and gas

An environmental strategy to reduce methane emissions in China’s energy sector will yield important economic, environmental and public health benefits. Methane is a primary component of natural gas, a precious energy commodity.

Constrained by limited domestic production, China imports 40 percent of its gas supply, and recently overtook Japan as the world’s top natural gas importer. The growth in gas consumption is projected to grow for the next 20 years as China seeks to expand the share of natural gas in its low-carbon energy transition. At minimum, cutting methane emissions will help avoid the waste of a valuable product; it may also improve China’s energy security by diversifying natural gas supply and reducing demand for imports.

As China ramps up natural gas use, attention is needed for the careful management of emissions from the gas supply chain. Otherwise, emissions from methane leakage could negate the climate benefits of replacing coal with gas. The natural gas leakage threshold is about 2.7 percent, but depends on the country-specific power plant efficiencies among others. If methane leakage exceeds the threshold point, then switching from coal power to natural gas could be worse for the climate.

Methane also contributes to ground-level ozone, a harmful air pollutant that exacerbates the very air quality problem the government is grappling with. As the country works to scale up its shale gas production, co-control of methane and air pollutants will receive increasing public scrutiny. Last but not least, more methane recovery will also replace more coal mining and reduce associated pollution.

Progress has already begun

Back in 2016, China’s top climate policy think-tank proposed to include methane emissions from China’s energy sector in the 13th Five Year Plan (2016-2020). While the recommendations did not make it into the document and methane management in China still remains nascent, industry and government leaders are beginning to step up on this issue.

For example, China National Petroleum Corporation (CNPC), the world third largest oil company, has joined 12 other global producers whose CEOs have pledged to limit emissions of the potent greenhouse gas from their oil and gas operations to 0.25 percent of total marketed product by 2025. And Beijing Gas, the capital’s natural gas distributor has signed on to a set of Methane Guiding Principles.

Meanwhile, Senior Chinese policy leaders pledged to strengthen control of non-CO2 greenhouse gases; and called for a deeper understanding of methane emissions to accelerate the low-carbon transition of China’s oil and gas industry.

Opportunities ahead

According to the International Energy Agency, the global oil and gas industry could reduce methane emissions by 75 percent using existing technologies – with up to two thirds of these reductions at zero net cost. Application of digital technologies, a field in which China enjoys a global edge, could unlock huge potential benefits through large-scale methane emissions reduction efforts along the oil and gas supply chain.

At the same time, satellite remote-sensing technologies like MethaneSAT – a mission being developed by EDF and due to be launched in 2021 – and the GOSAT used in the study referenced earlier – offer exciting additional tools for China and other countries to identify, measure and verify methane emissions.

A comprehensive, reliable inventory of methane emissions based on strong science is an essential step to achieving effective emissions reductions goals. To realize these reductions China should also establish specific methane reduction targets for the energy sector, and ensure that emissions data is both transparent and verifiable.

Improving methane abatement efforts in China could also have a global impact. Given China’s status as a major purchaser of natural gas and an investor in the industry, domestic standards could be leveraged to influence methane management practices of China’s oil and gas suppliers globally.

The next five year plan

As China gets set to develop its 14th Five Year Plan (14th FYP, 2021-2025) and prepares for the communication of its revised nationally determined contribution by 2020 under the Paris Agreement, there is an important window for the government to consider including a methane emissions target for its energy sector in the blueprint document.

Given what we are starting to learn about China’s methane emissions, launching a comprehensive scientific study based on empirical data of the Chinese energy sector’s methane emissions as part of the 14th FYP preparation process would be enormously helpful. An improved inventory based on strong science will help inform the establishment of an effective and stringent methane target in the new plan.

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¹Yang, L., Zhu, T., and Gao, Q. 2014: 2. Technologies and Policy Recommendations For Emission Reduction of Non-CO2 Greenhouse Gas From Typical Industries in China. Beijing: China Environmental Science Publishing House.