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China Push into Synthetic Natural Gas Has Pollution Consequences

Burning synthetic natural gas may be cleaner, but making it results in enormous greenhouse gas emissions
Smog over Beijing's Forbidden City



Wikimedia Commons/Brian Jeffery Beggerly

When the Chinese government recently folded to public outrage over Beijing's record-breaking levels of smog, some thought it could signal a forceful shift to clean energy in the country.

Instead, it looks like it might do the opposite.

China is in the process of approving a new fleet of large-scale, coal-fueled synthetic natural gas (SNG) plants to be built in northwestern China and Inner Mongolia, projects that would emit seven times as much greenhouse gases as conventional natural gas plants, according to a new study out in the journal Nature Climate Change.

Nine projects have been approved; two recently completed the first phase of construction, and two more recently began construction. On Aug. 20, the first SNG plant in Xinjiang began piping natural gas eastward.

According to the study, assuming use of 90 percent of production, the nine approved plants would emit 21 billion metric tons of CO2 over their 40-year lifetimes. Conventional natural gas plants would emit 3 billion metric tons over the same period.

There were more than 30 proposed SNG plants in China in 2012, according to the paper's authors, Chi-Jen Yang and Robert Jackson of Duke University.

"The scale is massive," Jackson said. "If these plants were to be built, it would have enormous greenhouse gas consequences."

Officially 'clean energy'
SNG plants, which burn coal to create natural gas, first came under government regulation in 2010, at which point the National Development and Reform Commission (NDRC) put a hold on all but four proposed projects.

Earlier this year, however, the NDRC approved five more. And earlier this month, after Jackson and Yang submitted their paper, the NDRC approved seven more SNG projects, according to the state news agency Xinhua.

The reasons for this sudden shift were both environmental and economical, according to Jackson.

No country has more coal than China, and no country consumes as much of it. Prices recently reached their lowest point since 2009, however, and the Chinese government only recently started taking price controls of natural gas. Unconventional gas development is still trying to get going in the country, supplying 4 percent of China's energy, according to the EIA.

One way to increase demand for coal is to expand SNG development.

"It's been less profitable to go after natural gas than make natural gas out of coal," said Jackson. However, demand for natural gas is set to increase.

The Chinese government recently came under heavy criticism earlier this year for Beijing's very public, record-breaking smog levels that smothered the city for days (ClimateWire, Sept. 4).

The government has responded by announcing the Beijing 2013-2017 Clean Air Action Plan and national Air Pollution Control Action Plan, both of which mandate cuts in levels of coal consumption and PM 2.5 (particles smaller than 2.5 micrometers in diameter) in Beijing. Both plans classify SNG as a source of clean energy.

With China's conventional natural gas industry still finding its feet, the simplest way to meet this demand is with SNG. And as long as the coal is being burned away from urban areas, it's classified as clean energy, explained Yang. "In a way, the classification makes sense, because you move CO2 away from population centers."

Jackson and Yang also criticized SNG projects for their intense water use. The nine approved plants are being constructed in desert environments in Xinjiang and Inner Mongolia, and SNG production requires 6 to 12 liters of water per cubic meter of gas, compared to shale gas, which -- while frequently lambasted for its impact on water resources -- needs 50 to 100 times less.

Locking in a water shortage
The nine approved plants would consume more than 200 million metric tons of water annually, assuming operation at 90 percent of production capacity, exacerbating an already significant water shortage in the region.

The study pointed out the massive financial investment. Over the next three years, it's estimated government SNG investments will total 240 billion yuan -- and could also have environmental impacts.

Jackson and Yang wrote in their paper that "operation of the plant would probably continue even with low or no profitability," an effect they called "technological lock-in."

"You don't make billion-dollar investments and just shutter properties," Jackson said. "Once these plants are built and operational, they'll be used for 30 to 40 years, regardless of environmental consequences."

According to Jackson and Yang, the only way these projects could be environmentally justifiable is with the implementation of carbon capture and storage (CCS) technology.

Yang said it would be easier to separate CO2 during the coal-to-gas process than with a purely coal-fired power plant. None of the proposed projects makes mention of CCS, however.

"One argument for using technology like this is because it allows you to capture CO2," said Jackson. "But none of [the] projects that have been completed or are under construction have CCS or have been designed with CCS."

CCS is as costly in China as it is anywhere else in the world, but Jackson said the Chinese government still hasn't indicated if it will invest in the technology.

In the meantime, news reports state that the number of proposed SNG projects has grown to more than 40 in 2013. Those facilities would have a total capacity of nearly 200 billion cubic meters a year of natural gas -- far exceeding China's total natural gas demand -- and potential emissions of roughly 110 billion metric tons of CO2 over 40 years, according to the study.

"It's kind of scary, the speed they are moving," Yang said. "I feel like I really have to say something."

Reprinted from Climatewire with permission from Environment & Energy Publishing, LLC. www.eenews.net, 202-628-6500

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