She and many other experts believe coal can only be made environmentally sustainable through the more experimental technology of capturing carbon dioxide emissions and storing them underground.
A joint government-private project in the United States aims to build such a "zero emissions" plant by 2012. Separately, Xcel Corp. of Minneapolis, a major electric and natural gas utility, is studying building a carbon capture and storage power plant in Colorado.
Across the Atlantic, the European Union may require carbon capture and storage systems for all new coal-fired power plants, with a proposal expected by year end. The gas would be buried in aquifers, depleted coal mines or geological faults deep underground.
But the costs are daunting.
"It takes a lot of money since you have to go so deep," said Brock of Cambridge Energy Research Associates. "There is not one commercial carbon capture and storage project yet. It's yet to be proven."
With such high costs, few utilities will embrace these technologies without a strong push or subsidy from government. The U.S. Congress is weighing several proposals, but their fate remains uncertain.
The degree of public support for such policies remains unclear. Consumers may balk at having to pay more for electricity from "clean coal" plants, either through higher rates or taxes.
But there is growing awareness of the problem. In both the West and India and China, traditional utilities and new players are investing in wind and solar power. A subsidiary of coal giant Shenhua is building a 200-megawatt wind farm in the waters off China's east coast.
"The goal is to raise both efficiency and turn to renewables while backing out of coal in the process," said Lester Brown, president of the Earth Policy Institute, an environmental think tank in Washington. "The question is, can we move fast enough?"
Meanwhile, in Jungar Qi, the house-sized mine trucks rumble on, rushing their multi-ton loads of coal to railways and coal yards. The biggest landmark in the city — the two huge smokestacks of its coal-fired power plant.