Friday, January 05, 2007

Part II: China's Coal Future

To prevent massive pollution and slow its growing contribution to global warming, China will need to make advanced coal technology work on an unprecedented scale.

By Peter Fairley

A billboard exhorts construction workers building Shenhua Group’s coal liquefaction plant in Inner Mongolia: “To make a better future we must work hard for the project of making coal into oil.” Credit: Peter Fairley

Multimedia • How Gasification Works

Other readers liked: • The Precarious Future of Coal 03/14/2007 • Picking a Winner in Clean-Coal Technology 03/19/2007 • A Practical Use for Waste Methane 02/27/2007 • Zero Tolerance for Carbon-Dioxide Emissions 02/28/2007 • White House Budget to Cut Energy Research 02/09/2007

To read Part I of this story, click here.

Carbon Power

While China's desire to end its dependence on foreign oil is helping to drive huge capital investments in liquefaction technology, the country's power producers are moving much more slowly to take advantage of coal gasification. What they, like their American counterparts, are missing is an incentive to upgrade from conventional pulverized-coal plants to the more expensive gasification plants. According to Li Wenhua, the former 863 program manager (who now directs gasification research in China for General Electric), Chinese industrialists perceive pulverized-coal plants as a license to print money. "People say you shouldn't call it a power plant; it's a money-making machine," says Li. As yet, no power company has been willing to be the first to hit the off switch.

Ironically, China's move to a more open economy has hampered efforts to deploy more innovative technologies. In the 1990s, it looked as if China's power sector was headed for its own gasification revolution. In 1993, China's leading power engineering firm, China Power Engineering Consulting in Beijing, began designing the country's first gasification power plant. The monopoly utility of the era, the State Power Corporation, planned to build the commercial-scale plant in Yantai, a thriving seaport not far from the Bohai Sea. The Yantai plant was to be the beginning of a transition to cleaner coal technology, says Zhao Jie, the plant's designer, now vice president of China Power Engineering. "China wanted to take a cleaner and more efficient way to produce power," says Zhao. Instead, the demonstration plant she designed went on a roller-coaster ride to nowhere. Design work was temporarily halted in 1994 when the cost of the technology was deemed unacceptably high, revived in the late 1990s, and then cut adrift after 2002 by the breakup of the State Power Corporation.

The Yantai power plant was based on integrated gasification combined cycle (IGCC) technology. IGCC plants resemble natural-gas-fired power plants--they use two turbines to capture mechanical and heat energy from expanding combustion gases--but are fueled with syngas from an integrated coal gasification plant. They're not emissions free, but their gas streams are more concentrated, so the sulfurous soot, carbon dioxide, and other pollutants they generate are easier to separate and capture. Of course, once the carbon dioxide--the main greenhouse gas--is captured, engineers still need to find a place to stow it. The most promising strategy is to sequester it deep within saline aquifers and oil reservoirs. In preliminary analyses, Chinese geologists have estimated that aging oil fields and aquifers could absorb more than a trillion tons of carbon dioxide--more than China's coal-fired plants would emit, at their current rate, for hundreds of years.

The Huaneng Group, a power producer based in Beijing, has pulled together a consortium of power and coal interests (Shenhua included) called GreenGen to build the first Chinese IGCC demo plant by 2010; like the related ­FutureGen project organized by the U.S. Department of Energy, GreenGen is to start with power production, then add carbon capture and storage. China's vice premier, Zeng Peiyan, made an appearance at GreenGen's ceremonial debut last summer, indicating Beijing's support for the project.