IEEE Spectrum: In April China started operating its first coal-gasification power plant, called GreenGen. Gasification uses heat and pressure to convert coal into a mixture of gases, which are then burned to drive turbines. Gasification is more efficient in converting coal to power than direct combustion is. In addition GreenGen was designed to support an additional process—capturing carbon before it enters the atmosphere. Because of China’s dependence on coal, proponents say it’s a good place to test the technology. However, many gasification projects have been plagued with cost overruns and delays, and critics point out that the environmental liabilities of trying to dispose of the carbon and other byproducts of coal burning are yet to be clearly evaluated.